7.62 NATO vs .308 Winchester Ammo, What’s The Difference?

Gun nut, Tom McHale, risks a fight to explain the subtle nuances between 7.62 NATO vs .308 Winchester Ammunition.

Can you shoot .308 ammo in a 7.62 rifle? Or is it the other way around?
Can you shoot .308 ammo in a 7.62 rifle? Or is it the other way around?

Tom McHale

USA –-(Ammoland.com)- If you want to start a good bar fight, ask about a saloon full of gun people about the differences between .308 Winchester and 7.62x51mm NATO. We’re going to dive into the fray with a simplified and practical explanation. Ready?

  • They are different.
  • They aren’t different.
  • They might be different.

OK, so that was a bit of a wise guy response, but those statements are all quite true. Don’t worry, we’ll explain further. However, we’re going to try to do that in such a way that you don’t want to bash your own brains out by having to read about the nuances of things like piezo transducers.

Let’s look at a few categories of comparison, then we’ll sum things up.

7.62 NATO vs .308 Winchester – History

Doing the 1940s and early 1950s, military rocket surgeons wanted to improve the effectiveness of the M1 Garand rifle and its .30-06 cartridge. One contender, more suitable for higher capacity box magazines was a modified .300 Savage design called the T65. While specs varied throughout development, it ended up as the earliest iteration of the 7.62x51mm NATO. But, as usual, the commercial market was more nimble, and Winchester launched the .308 Winchester in 1952.

It took the government until 1957 to have a cartridge and rifle hitting the barracks with similar specs.

7.62 vs .308 – Pressure

Here’s where some of the confusion comes into the picture. Maximum pressure numbers thrown around for the two calibers are often shown as 50,000 “psi” for 7.62 and 62,000 psi for .308. At first glance, that appears to be a big difference and a potential reason why folks might consider it unsafe to fire a “higher pressure” commercial .308 cartridge in a rifle built for 7.62x51mm NATO.

While commercial .308 ammo may have slightly higher pressure than 7.62x51mm NATO, it's really the brass and chambers that are the issues to understand.
While commercial .308 ammo may have slightly higher pressure than 7.62x51mm NATO, it's really the brass and chambers that are the issues to understand.

As with most things, the devil is in the details. I put that 50,000 “psi” number in quotes because it’s wrong, at least when shown with a pounds per square inch label at the end. That 50,000 number is actually an accurate representation of copper units of pressure or CUP. A far less precise way to measure pressure, the method literally relies on looking at how much little copper disks compress when you fire the gun. While there isn’t a consistent mathematical formula that equates CUP to pounds per square inch (PSI) across the board, the difference in this specific case is somewhere around 8,000. In other words, the maximum pressure for 7.62x51mm NATO is about 58,000 psi – not all that far from the 62,000 figure for commercial .308 Winchester.

As both loads are routinely proof tested at far higher levels, this 4,000 isn't a difference that's going to alter the trajectory of Michael Moore's daily Krispy Kreme run.

7.62 NATO vs .308 Win – Case thickness

Measuring the thickness of cartridge cases is kind of a pain, especially since I tend to mash them all up when trying to cut them in half with my Dremel tool. So, I took the shortcut to illustrate the difference. From my big bucket of .308 / 7.62 brass, I selected some representative samples of both commercial .308 Winchester and 7.62x51mm NATO brass and weighed them. I picked several of each and averaged the weights. I didn’t measure the cases because they’ve been fired, so that won’t tell me much other than the general size of the chamber from which they went bang.

  • Hornady .308: 169.6 grains
  • Winchester .308: 163.3 grains
  • Lake City 7.62x51mm NATO: 183.5 grains

That’s a significant difference! Thicker walls combined with similar exterior dimensions means less powder capacity and a lower “top end” and all else the same, lower pressure and velocity.

The thicker brass of 7.62 cases is a significant factor for the reason we'll discuss next.

7.62 NATO vs .308 Winchester – Headspace

Last but not least we get to the real difference. Military rifles for 7.62x51mm NATO can, and usually do, have longer chambers. In things like machine guns powered by ammo made all over the world, there’s got to be some slack for reliable feeding and operation with all that violence going on during the feeding and ejection process. The solution is to make the chamber headspace a bit longer. If you’re not familiar with headspace, think of it as the distance from the bolt face to the point in the chamber that stops forward motion of the cartridge case. If chamber headspace is too long for a cartridge, it will float back and forth in the chamber. If headspace is too small, the bolt will not close properly or will require excess force to close.

How much different is the headspace? The .308 Winchester chamber headspace is between 1.630 and 1.6340 inches. The 7.62x51mm NATO is between 1.6355 and 1.6405 inches. While the published numbers show about six-thousandths of an inch difference, it’s not unusual for the headspace in a surplus 7.62 rifle to be 10 or even 15 thousandths longer than that of a commercial .308. That doesn’t sound like a big deal, right up to the point where you fire thinner commercial brass in a long-chambered rifle. The brass will stretch, possibly enough to contribute to a dangerous case rupture. Doing the same thing with thicker military brass is no big deal and the way the system was designed. Thicker brass can handle some extra stretching into a longer chamber throat, so it's no big deal.

The solution to the question is to know your rifle and what its headspace really is. Only then will you know if its safe to shoot commercial .308 Winchester ammo in a 7.62 chamber.

Figuring out if your headspace is safe is a fairly straightforward deal. You can order a set of .308 Winchester Go / No-Go headspace gauges. After removing extractors and/or ejectors as appropriate in order to remove all sources of tension, use the gauges to check the chamber size. The bolt should close easily on a Go gauge and not close on a No-Go gauge. A third type, a Field Gauge checks the maximum published chamber size. With some 7.62 rifles, you might find that the bolt closes on the No-Go gauge. As long as the bolt won't close on the Field gauge, you're still within maximum published limits.

The net-net-net

Technically speaking, in terms of specifications, there are differences, but mainly in the chambers of rifles designed to fire each cartridge. 7.62 brass is a bit thicker, and commercial .308 is sometimes loaded to slightly higher pressure, but other than that, the cartridges themselves are pretty much the same.

If you want to be ultra safe and conservative, fire only 7.62x51m NATO in 7.62 chambered rifles and .308 Winchester in .308 rifles.

Next on the “risk” spectrum is the scenarios of using 7.62x51mm NATO ammo in a .308 chamber. In theory, you might run across ammo that’s particularly long. Ammo might not chamber at all or might require undue pressure to the chamber. That could result in dangerously high pressure. In reality, that would be really unusual. While 7.62 ammo could be significantly longer, that's a pretty rare thing, at least to a significant level, so most people don’t consider it a big deal to use 7.62 ammo in a .308 chambered rifle.

Where you need to be careful is using .308 Winchester commercial ammo in a 7.62x51mm NATO chambered rifle.

While most modern 7.62 chambers are probably fine as they tend to be cut closer to .308 dimensions, it’s always safest to know exactly what you have in terms of headspace. If your rifle has long headspace, stick to 7.62 NATO ammo – don’t use commercial .308.


Tom McHale is the author of the Insanely Practical Guides book series that guides new and experienced shooters alike in a fun, approachable, and practical way. His books are available in print and eBook format on Amazon. You can also find him on Google+, Facebook, Twitter and Pinterest.

  • 173 thoughts on “7.62 NATO vs .308 Winchester Ammo, What’s The Difference?

    1. I prefer .308 and .243 for mid to long range. I like .223 and 5.56 but lets face it. The AR-15 ammo is a girls round.

    2. A few thoughts and personal experience with factory loads, those being 1966/1967 FA Match caliber 30-06 v. carefully assembled hand loads, individual weighed charges using Sierra 180 grain Matchking bullets, and Military Match Brass, as I recall. At 600 yards the FA ammunitation outshot my hand loads.

      Otherwise, with the 308 in bolt action target rifles, I simply could not shoot 1000 yards. DIfferent story with the ’06. Except for very limited use of IMR 3031 in a Remington 40x Rangemaster, I used mostly IMR 4895. At one point, latched onto a bunch of WC846, which aside from a now and then muzzle flash, shot very well for me in my bolt guns at 200 and 300 yards. It was a surplus ball powder, and metered very consistently. Enough said.

      1. Alan, I currently use IMR 4350 in both 30-06 and .308. The charges are from an old Speer reloading manual printed before lawyers. I shoot 55.0 grains under the Sierra 180 grain gameking or the pro-hunter spitzer in the 30-06, and it chronographs at about 2700 from a 22 inch Ruger M77MKII. From a 24 inch barrel, I get about 2770fps. The Gameking will stay supersonic to about 1200 yards at sealevel. Both bullets stay supersonic past 1000 yards here at the Front Range in Colorado, where the altitude is around 6,000 feet or higher above sea level. The .308 is also flatter and retains more velocity up here.
        What barrel twist did your .308 have? I know some of the target rifles had/have a 1 in 12 rifling twist, some of the M1As have a 1 in 11 twist, and most hunting rifles (some target rifles) have a 1 in 10 inch twist for the >308 win/7.62 X 51. I think the 1 in 12 twist rate may be slow enough that at low altitudes the bullet would lose stabilization when it went sub-sonic. I know the Army uses a 1 in 10 in. twist rate in its sniping rifles just to avoid that. They also use the Sierra 175 grain Matchking for their projectile because it will stay supersonic to about 1100 yards (1,000 meters) from a 22 inch barrel. Velocity for this load is still given as about 2550fps. I get about 2600fps from my Remington SPS Varmint rifle.
        SSG Elton P. Green, USA, Inf., (Ret.)

        1. Elton:

          Hope this finds you well. The rifling twist in my 40 X Remington Rangemaster was originally 1 in 10″. It was a stainless steel barrel, a bit north of 27″ long as I recall. When I rebarreled it, with a Douglas Chrome-moly Premium Air Gage barrel, it was also 1 in 10″ twist. Model 70’s in .308 caliber were 1 in 12″ originally. When rebarreled they were 1 in 10″ , also Douglas barrels, as above described, and 24″ long, x .750 – .800 diameter at the muzzle. A Model 70 so set up weighed, as memory serves, between 10 and 11 #, which I thought was quite nice for a Left Eyed Shooter.

          On scope sights, and a recent comment of yours, the only scopes sights I ever used were Unertle Target Scopes. First one was 12 x 2″ diameter, which I found to heavy. I exchanged it for a 10 x 1.5″, which suited me much better. Actually, I preferred to shoot Iron Sights, Redfield Olympic rear, and apature front. I felt putting that Unertle scope on a rifle destroyed it’s balance, though they were excellent sights I thought. Also, wonderful people to deal with re repair. The vertical cross hair on my scope sight broke, years after pu chase, don’t know how or why. They fixed it in about half an hour, while I read a magazine, and charged me 15 or 20$, including adjustments and “clean up”. enough ancient history.

          Funny thing about those two makes of rifle, the Model 70 and the 40X. My Model 70’s were all post 1964 type. I had to really heve on the bolt of the 40X to cycle it, whereas running the Model 70 bolt was a 1 finger, my left thumb operation. Years ago, at a rifle match in Ohio, one shooter asked me to try his Springfield. Working the bolt on Springfields always struck me as a chore, and I so stated. This fellow sort of chuckled, and again said to try his Springfield. Dry fire it once he said, handing me the rifle, action open. I closed the action, decocking the rifle. I then worked the bolt. Never saw a Springfield like that one. The fellow then directed me to look at the cocking cam. It was the twin brother of the cocking cam on a Model 70. and I thought really quite amazing. The original cam had been welded up and recut, the guy said. By the way, re ancient history, did you ever happen on any of the LEFT HAND ’98 Mauser Rifles P. O. Ackley was importing from Japan prior to GCA ’68, complete with charger slot? Take care.

        2. Elton:

          For reason or reasons unknown or forgotten, perhaps never tried, honestly do not recall, while I used 4350 in the 30-06, I didn’t for the 308 Win. I generally used IMR 4895. Also WC 846, a surplus ball powder that worked very well for 200/300 yards. Muzzle flash was, at times, quite prominent, and the report varied from a sharp crack to a dull thud. That said, it produced quite accurate loads, and at 50 cents per pound, one could hardly complain about muzzle flash, which never bothered me in any case. Scorers did comment on it though. Never having had a chronograph of my own, and way back when I was shooting high power rifle, not having access to one, I used handbook data and test firing. I expect that my handloads were generally moderate in nature. Take care.

    3. Mr. Romeu, I don’t doubt that at the Camp Perry matches you witnessed numerous malfunctions due to equipment and ammunition. Personally, I would expect that to happen, especially on the first day. I have no doubt that many of the competitors on the first day are competing for the first time, or are new to long range competition. Nor do they necessarily have the money to field top of the line equipment. I know I don’t. Most of the competitors aren’t there to win that match. They’re there for the experience of having shot just once in a national match. They’re there to test their equipment, to meet the other shooters (especially those that are nationally rated) and they’re there to enjoy the experience.
      As to the 600-1000 yard targets, and shooting into the front berm, I would think you would expect some of the competitors to shoot low at least the first time. I expect that there are a number of first timers and beginners in long range rifle who shoot a little low at 600 yards to begin with. I don’t know what state you are in, but here in Colorado, I know of only one range that is public where one can shoot 600 yards or beyond, and they only provide steel targets at that distance. (Cheyenne Mountain Shooting Range at Fort Carson). Fort Riley, Kansas also has a 1000 yard POF range, but its not open to the general public. A range with butts and bullseye targets for practice where one could go to shoot is like finding hen’s teeth in most states. The range I belong to does have target butts out to 600 yards but I can’t practice regularly beyond that because the range doesn’t support anything beyond 600 yards. In most states, KD ranges with bullseye targets out to 1000 yards are nearly non-existent. Of course they’re going to shoot low at those ranges. By the way, the Army and the Marines don’t normally shoot factory anything at those matches. They nearly always use “their own special concoctions”. In other words, the armorer on their team (and some of the most experienced shooters) tend to load their own rounds for both of those matches. In the case of the 1000 yard matches, some of the teams even build the rifles used. Also, if you demonstrated the attitude there that you do in this discussion forum, I’m sure you detracted from numerous of the competitors’ enjoyment of what was supposed to be a fine old time. So if you don’t want to have the even tenor of your day disturbed by things like weapons malfunctions and being showered with dirt in the 600 yard target butt, don’t assist in running the range, because having those things happen at a competition is just part of he job.
      Elton P. Green SSG USA, Inf. (Ret.)

      1. I don’t know what Camp Perry this puke shot at. The nationals are held all summer long every year. He would most likely get his ass kicked or invited to leave or both.I’ve shot at Perry both as a civilian and as a Marine. As a civilian you can use what you want that meets the rules allow. As A Marine Corps shooter we used the weapons and ammunition issued. If not you at least you won’t shoot anymore. If you damage a rifle wwith your own loads and you don’t shoot anymore and end up with an NJP for disobeying an orde. The AMU at Stone Bay. N.C. assembled all of the special ammunition for compition if using the .300 win mag or other no standard ammunition. They where assembled 1 round at a time with the specific formulas specifically for the use intended. All of the rifles designed for compition as well as combat are produced there as well. Marine competitors used only what’s issued. If 7.62 rifles are issued 7.62 match ammunition is issued. Issued equipment is all you can use in service rifle matches. CMP rules are specific that military shooters must only Government issued equipment. Marine armorers are trained to build these service rifles for match shooting. This is a full time MOS. The only rifles I’ve ever seen destroyed where civilian shooters using improperly assembled hand loads. M1A and AR15 commercial or surpluses M1s. Out of battery detonation or case head failure.

        1. Mr. Furbush: I know that at one time, the Army was hand loading the Sierra 240 grain MatchKing for some of the Nationals. I was told that they tried some in some of the M1A rifles and found that the bolt acceleration was too great, even though the pressures were in spec. I heard but can’t confirm that they cracked some of the receivers. I don’t know why anyone would use that heavy a bullet for 600 yard matches in the 7.62/308. I would think the velocity loss would outweigh any gain in B.C. I don’t know if they used it in the .300 Winmag. I knew that the Army Marksmanship Unit had a hand in assembly of the rounds used in the 1000 yard matches. I’ve seen shooters put rifles out of action due to malfunctions which couldn’t be cleared short of a shop on several ranges, both civilian and military. Seems like its nearly always out of spec ammunition or badly assembled reloads. Sometimes its someone who modified their rifle or pistol without the skill to do it right. Sometimes its been primer sensitivity issues causing a slam fire or out of battery detonation. I can say that when you get two or three hundred shooters on the range, there will be some malfunctions and that should be expected. Most will be minor malfunctions, but they will happen and having a poor attitude about it as an official just shows petty arrogance. If I were the range master and saw such an attitude displayed by an official, I’d have him removed from the range until he learned better. And as the Range NCOIC, I have done that to both NCO’s and officers.
          Elton P. Green, SSG USA. Inf. (Ret.)

        2. @Mr. Jack a Furbish, by God if it wasn’t for you, the Marine Corps would never survive! I have the same advice for you that I gave to Mr. Elton P Green. you need to write it down your attitude a few notches and go back and reread exactly what I wrote or get some grade-schooler to teach in the English language.

          If you ever bother to crack a dictionary,, look up the definition of “primadonna”. You two would fit real nice into that category. You shoot from the mouth first before you site in your targets. In the Marine Corps Infantry you’re the ones that would be watched by the squads because you would be the most dangerous. You think you know it all and in the end run you don’t know jack or schitt and you’re the type that ends up getting people hurt or killed thinking that you’re going to win the war all by yourself!

          Now be a good little jarhead and go back and reread what I wrote!

          1. How about you go fuck yourself. I doubt you’ve ever been to the Nationals let alone ever actually fired a live round on any organized rifle range. Your Piss poor attitude would get you kicked of all of the ranges I shoot on these days. I go out for state team try outs every year. I’ve only missed Camp Perry 4 times sense 1996. That was because of working as a contractor for Black Water security, in Iraq&Afghanistan. Twits like you would get a bullet by the 3rd time out. Most range PMI and SO Personal are there to assist new shooters and run a safe line. You would end up getting your ass whipped one evening after chow running that sucks hole under your nose the way you do. If you work a firing line the way you work this this page you wouldn’t be invited back after the first day. All PMI and RO personal get the conduct and range rules breef the day before. This covers it all, turds like you are definitely a no go. I’d like to crack a dictionary over your flat head. The last thing the shooting world needs is an ignorant cock sucker like you. I’ve seen a thousand FuckTards like you.

            1. Jack, that was a waste of a bunch of truly accurate and excellent descriptive words on someone who won’t learn anything from them. And he wouldn’t get shot the third time out, because he’d be sent home after the first time, provided his arrogant, self-important, undeserved superior attitude didn’t get him killed in first encounter; you know that. I saw lots of guys get their walking papers that way in Afghanistan, if they didn’t get killed by a local because they offended his honor. He wouldn’t have lasted a week. One of the locals at FOB Sharanna or Shank would have brained him with a wrench. At Bagrahm, somebody would have buried him in a ditch. Blackwater, huh? Good group, badly treated and maligned. Knew some of them when I contracted.
              SSG Elton P. Green, USA Inf. (Ret.)

          2. Actually, Mr. Romeu, if it weren’t for men like Jack, the Marine Corps wouldn’t have survived. If you think what we did for a living was fun, watch ‘We Were Soldiers Once’. That is a pretty good depiction of close combat. Our job was to keep cohesion at the squad, platoon, company and battalion level. If we did it right, most of our men survived most of the time. If we did it wrong both they and we died. Sometimes we died anyway. Every single day we served in either the Army or the Marine Corps, we could be REQUIRED to lay down our lives for our men, from the lowliest private to the general. And sir, we would have. We still would. I don’t know if you ever served in any of the armed forces, but if you did you didn’t learn much about Combat Arms. As to being the most dangerous person in my squad, platoon or company, the only person more dangerous than me in C Co, 1/12 Inf, 25th Inf Div (light) was my First Sargeant, now CSM Charles Fitzpatrick, (Ret.). He was a Vietnam Vet, and an artist with the M60. 3 years as a Huey door gunner does that. By the time I was promoted to E-5, I shot expert with every weapon in the inventory, helped teach hand-to-hand, and could sneak up on a sentry and kill him with my hands, a knife, a garrote or a vanadium steel spike without making a sound. When I went to Korea and patrolled the DMZ I was the sniper and the point man for combat patrols. I could set, sight and arm a Claymore mine in about 3 minutes on a bad day. I could slip through enemy lines with a PRC77 or Singars radio and call for fire from the Artillary without them even knowing I was there until the rounds impacted. And if Jack was Marine Infantry he did all this and more. If he was Recon, he was one of the most dangerous and deadly men you would ever meet. Our job was to kill people, period. We did that all over the world. Our job was to teach other soldiers and marines to kill people from nose to nose out to the maximum range of our farthest reaching weapon system, in my case the M242 25mm Chaingun, about 3000 meters. Our sole purpose in life was to be the most dangerous people in any combat zone, in any unit and anywhere the US Govt. sent us, and you DAMN BETTCA we were. We had to be the most dangerous and deadly ones around for men to willingly follow us to what looked like certain death. We had to be so because the men under us and the inexperienced LTs we were charged with teaching had to believe we would be able to lead them in and get them out alive. We were life takers-that was our job. And men followed us because they were convinced that we would KILL anyone who tried to kill them or us. And they knew that if their NCO was the best man to accomplish the deadly mission, he wouldn’t send someone else out just to avoid a little danger. Sir, every NCO worth his salt lives by the motto I live by: Mission, Men, me. Sir, you are correct in one thing. We (all of us) are the most dangerous and deadly men and women you will ever meet. Oh, and I did read your comment carefully, what I said stands, and I have three college degrees, just so you’ll know. Also, I have run a couple hundred ranges in and out of the Army, from machine gun ranges, pistol ranges, rifle ranges, and hand grenade ranges to Tank and Bradley ranges. I know how its done and how to do it right. Hand grenade ranges are scary.
            Thank you Jack, for your answer. I didn’t want to use that language, but it pretty much sums up my opinion, too.
            Oh, and I’m not the deadliest one in the family. My youngest brother ran around with the SF and killed people in places that we were never in and still haven’t been. There are bodies in South East and West Asia and in Central and South America that still haven’t been found. And he did it good and came back with all his parts. Brought all his men back, too. He retired an E-7, too. HuuRaa.
            Elton P. Green SSG, USA, Inf. (Ret.)

            1. Hey there brother. Looks like both you and your brother and I soaked up a lot of the same swamp water and chewed the same dust. Like you two my job as a Recon Marine and PMC for Black Water was hunting and killing other men. Working in both the same box and the rock box I used a accurized SVD with my loads to kill Hadji and Russian & Romanian API rounds for other purposes. Your spot on about how US military people hang together in combat. That’s why we win and they lose. As advisers, military or contractor we showed em how it was done and pointed in the wright direction. If they lost, that didn’t make us look good. I stopped counting how many of those Haji fucks I sent to paridise. You know as well as I, it’s only the first one you don’t forget. I amused myself at that retards expense because I could
              He obviously has never been off the block. I never could abide a fraud and liar. In the US Military he would just have been reassigned. As a contractor he would have ended up with a bullet in the gut or a blade across the wind pipe. Some of the guys I worked with weren’t the stabilist boys, but you don’t have to like every body you play poker with as long as they know thire job. During the gold rush days he probably could have bullshitted his way into a contractor slot but I doubt he would have lasted his first 10 days. He just don’t pack the gear. One of the joys of being a contractor was we didn’t have to live by those bullshit rules of engagement. No oversight, no problem. All that bad press was free advertising you couldn’t buy. Maybe one day our paths will cross and we can swap some sea stories and drink some good scotch. Siempre Fi

            2. Jack, I did all mine in the Army. When I was contracting, I couldn’t get a shooter job, and had to work for KBR and Fluor as a mechanic. They wouldn’t even let me touch a rifle. I got to meet some of the Blackwater guys at Al Asad, I think. I met and did work for several SF and Seal units over there and in Afghanistan, but always on the FOB. I tried to get a job with some of the security groups, but I was too old. So I fixed their vehicles and cussed because I couldn’t do what I was really trained for. But the Army let me do my job over most of the world at one time or the other. My brother did his stuff all on active duty, too. Didn’t want you to get the wrong impression. I have a good friend in Kansas who retired E-8 who did 4 or 5 tours in the sandbox as Nat’l Guard and used a couple of SVD’s while he was there. Don’t know exactly what province, or which FOBs because of OPSEC. And yes, in combat, I used guys like our friend as cannon fodder if they didn’t change their atitude. Love to swap stories over a beer sometime. Siempre Fi, sir.
              SSG Elton P. Green, USA, Inf. (Ret.)

          3. I’d get a real chuckle watching a FuckTard like you his first day in a ground combat unit. You’d puke the first time I told you to saddle up. You’d probably Piss your panties when the bird lifted off the ground. You’d be shaking so hard you’d have all you could do to slap a magazine in your weapon when I gave the lock and load order. You’d shit your panties the first time a bullet snapped past your ears. If you actually managed to survive your first punch up with a real enemy contact I’d take a real interest in seeing you suffer. Ever time I needed a shit job done, it’s got your name on it. Every mid watch guard shift is yours. Why should I interrupt a good Marines sack time when I’ve got my whipping boy? I’d stick you with the most fucked up bunch I’ve got, you are bound to get zapped one your first week in county. With that attitude of yours you’d have Hadji shooting at you from the front, and your own shooting at you from the rear. As the Company Gy/Sgt I’m God all Fucking Mighty, I’m the only SOB that has an attitude or an opinion. You’ll find out real quick that a two way rifle range ain’t call of duty. I’ve got your number you Fucking prick, I’ve seen a thousand like you in my day as a Marine As a contractor and as a cop. You don’t last long, you just don’t pack the gear. Real world ain’t a target range or call of duty little girl

          4. Who the FUCK cares what you write about anything FuckTard? Nothing you flush out of that toilet under you’re nose is worth hearing. A shit bird like you ain’t never said word one worth reading.

      2. Elton:
        My first experience shooting at 1000 yards was in the early ’70’s, with a personally owned Winchester Garand. I had done reasonably well the previous day at 600 yards, this was not at The Nationals, but rather at one of the Ohio Rifle and Pistol Association matches held during the summer at Camp Perry. Making a long story short, I had fired 4 straight misses, calling for marks, when I wasn’t even hitting the target. The line officer whom I knew slightly was about to disqualify me, asked exactly what I was doing. I was about to offer a “smart response”, but thought better of it, simply stating that I was having a problem. The Line Officer cut me some undeserved slack, asking how I has done at 600 yards. Well enough I answered. He then told me to put 600 yard elevation on my rifle. I cranked the sight all the way down, then back up to 600 yard elevation. The LO then asked if I could count to 21. I said I could, and he told me to put 21 clicks more elevation on the rear sight. This accomplished, he advised me that since the wind was down, to “shoot the damned rifle”. I took a 6 O clock hold and broke the shot. The target went down, coming up with a hit in the black, this on the old 5V target. I finished the string scoring in the mid 90’s out of a possible 100, pretty good I thought. Anyhow, later that day, I caught up with the LO, asking where that 21 clicks of elevation came from. He politely asked in a has a copy of the old big bore score book. I one had and so stated.The LO kindly suggested that I might benefit from reading through it, paying particular attention to the bottom of page 7 as I recall, which contained Average Sight Change Data, based on 30-06 Match Ammunition. Sure enough, there stood or sat reference to 21 clicks of elevation, 1 minute clicks.

        I shot that Garand for a number of years, putting about 12,000 rounds of mostly hand loads through it. That rifle never failed me, though I did have to replace a broken firing pin. Eventually I went to bolt action rifles,mostly the Model 70 Winchester Standard Target Rifle, in 30-06 and 308 Winchester using Military Match Brass.Never could shoot 1000 yards with the 308. Different story with the 30-06. Of course, the 21 clicks of elevation, 1 minute clicks became 84 clicks of elevation using Redfield Olympic Sights. I used to shoot as well at 1000 yards with Redfield Olympic Sights, perhaps a bit better than with a scope sight.To damned old for that game now, a lot less gear to drag around shooting IPSC pistol matches, and not nearly so far to drive. More later maybe.

        1. Alan, the Army Manual for Sniper Training And Employment does that, too. It gives the bullet drop at sea level for the M118 Special Ball in clicks of adjustment per 100 meters for the M21’s open sights and for the issued auxiliary sights for the M24 system out to 1000 meters. I think the problem you may have had with the 7.62X51 Lake City Match at 1000 yards is velocity. The -06 has about 150 to 200 fps on most 7.62 loads. The Special Ball is rated for about 2550fps, where the -06 173 grain or 168 grain match ammunition ran around 2750 to 2800fps. The 7.62 would go sub-sonic at around 800 meters or about 875 yards in the M21 and only a little farther in the M24, due to the extra two inches of barrel. Sometimes, when the round dropped low enough in velocity, it could become unstable, especially at low altitudes where air density is higher. Another thing that would have effected your distance shooting with this round is rifling twist. A number of the match grade rifles produced have a 1 in 12 twist rate in this caliber to optimize them to the mid-weight match bullets. When the bullet drops below the speed of sound, its spin rate isn’t enough to keep it stabilized sometimes, especially at low altitudes. If I remember right, that’s why Carlos Hathcock used the 30-06 so extensively in Vietnam in leu of the 7.62 X 51. The Army has since gone to the M118LR round, using the 175 grain Sierra bullet, which stays supersonic out past 1000yards in the M25.

          1. Elton:

            Being an old, worn out civilian, I’m not familiar with the manual you mentioned. Also, the military model numbers you mentioned soft of confuse me. In general. I thought that the recent military sniper rifles all revolved around the Remington 700 Action, with special barrels, stocks and triggers. Scope sights too. Is that correct.

            My own personal battery was mostly post 1964 Model 70 Winchesters, calibers 30-06 and 308 Winchester/7.62MM NATO. I did have one Remington 40X Rangmaster, which was probably the most accurate 30 caliber rifle I ever handeled. As I shot left handed,

            the Model 70 was ever so much easier to handle than the Remington for across the course competition. With one Winchester 308 that I had, original factory barrel, 180 Grain Sierra Match King bullets, Lake City Match Brass, Winchester primers and 41 grains of IMR 4895, the rifle was pillar bedded, with Redfield Olympic Sights shooting prone with sling at 600 yards, I could consistently hold inside 10 ring elevation, loosing a few out one side or the other, misreading the wind at Camp Perry. With the 40X, trigger changed to Canjar, the rifle having been pillar bedded, and Remington’s target load, 39 grains of IMR 3031 or a worked up charge 4895, don’t quite remember, shooting over an ammo can topped with a sandbag, and a 10 power Unertle Target Scope, no wind, I shot a 3″ diameter spotting disc full of holes, ultimately hitting the spindle, which made a large hole in the paper target. This was NOT at Perry. As earlier mentioned, I could do reasonably well at 600 yards with a 308. as to 1000, forget about it. It might have been muzzle velocity, as you mentioned, but since I had no access to a chronograph back then, I didn’t have gray hair either, who knows. The one and only time I shot in The Nationals, I was loaned a Match M-14 by those nice people at Eirie Ordinance Depot, which I returned with thanks. Match Ammunition was issued at the firing line. Some shooters complained about vertical stringing, which I didn’t notice. I did manage to uphold my end of the stick in a team match. Essentially, after the Garand, I was a bolt gun shooter. When it came to rebarreling, Douglas Crome-Moly Premium Air Gage Barrels always worked well for me, and they were great people to deal with. CAmp Perry matches were always interesting, and the Gunnery Sergeants I ran into at Quantico were always gentlemen, though at times I may have tried their patience, there being few left handed rifle shooters. They used to have nice matches at Cherry Point, and Camp LeJeune too as I remember. If I had ever learned to shoot off hand, I probably would have earned a Masters classification, as it was, I ended up with an Expert classification. More than enough said by now, and if you have hungin through my ramblings, you must be easily amused and or a glutton for punishment.


          2. Alan, the M25 is an upgraded version of the M21 or accurized M14. The M24 is a bolt gun, made on the Remington action, either the 700 or the 40X action, with a Douglas barrel, I believe. The manual is a US Army pub. from around 1990 or so, can’t tell you exactly, because my son in law is currently using it to train Squad Marksmen in his Cav unit at Ft. Carson, and I won’t get it back from him for a few months. Its kind of the Ranger Handbook for Snipers. The scope on the M24 is normally a Leupold 10 power with a mildot reticle. The new sniper rifle is an updated AR10 type, and the SF is using a .300 winmag for some of their long range work. Calibers are 7.62 Nato/308 Winchester and 300 winmag. A lot of the ammunition is Federal Gold Medal Match in both calibers. (yep, they’re shooting .308 in their 7.62 bolt guns and gas guns.) On a side note, you might try RL 15 or CFE 223 in your .308. Average velocities with these powders tend to be a little higher.
            Elton P. Green SSG, USA. Inf. (Ret.)

      3. @Elton P. Green, You might want to go back and reread exactly what I wrote and readjust your attitude and answering me because you didn’t pay a damn bit of attention of what I said or either you just flat ass don’t understand the English language?

        1. I did read your article. I thoroughly understood your article. I also understood the attitude conveyed by the tone of your article. I understood your arrogance, your lack of charity, your self importance and your belief in your personal superiority over everyone who was shooting at the range at the time, with the exception of the female competitors. I expect you were condescending toward them also but didn’t admit it. (note the larger than 4 letter words here-see, I do both read and understand the english language) Also, the comments you made to SFC (ret.) Jack Furbush were unwarranted, without merit, foolish and uncalled for. (see, another group of larger that 4 letter words- I couldn’t even spell Archeologist or Anthropologist and now I are one.) As to being a primadonna, maybe, but we (Jack and anyone who has been shot at in anger) have paid in blood for the right to be one if we so choose.
          Elton P. Green, SSG. USA, Inf. (Ret.)

        2. Who the FUCK would ever care what you say? On every one of these forums there’s always one turd that has to run his suck hole about things he knows nothing about. In both my military and lawenforcement career I always took am interest in making them suffer until they pulled thire head out of their ass and got with the program or I could get rid of them

          1. Gunnery Sargent Furbush, I just realized I might have insulted you by referring to you as SFC. As you know, E-7 in the Army is a Sergent First Class, and I didn’t think about you being a Marine. So I do apologize for that. And thank you for your service. I hope you have many more years pulling triggers. From your comrade in arms:
            Elton P. Green SSG, USA., Inf. (Ret.)

    4. I would tend to use water capacity (w.c.) of the case versus weight to compare differences in interior case dimensions. This does not indicate where differences in internal case dimensions are located, i.e., head thickness, wall or neck thickness. But it would indicate that cases with the same outside dimensions, but with less w.c., would have higher pressure if loaded with the same amount of the same propellant, and with the same bullet loaded to the same overall cartridge length.

      1. You might want try using a fine grained sand or powder like cement and utilize that method of measurement rather than the water because you will end up leaving beads of water / weight. on the inside of the casing with any kind of liquid.

        1. Gregory:

          Re your concern over drops of water remaining in cartridge cases will heating water checked brass to 180-200 degrees F. which will cook off any remaining water harm the brass for reloading?
          In my experience the answer is that it won’t or at least I never experienced any reloading problems with heat dried brass. Note, I was careful with temperature.

      2. Ibrac, you probably know this, but water is the method used by the manufacturers to measure case capacity. That’s because water is the basis for volume and weight in the metric system. One cubic centimeter of water weighs 1 gram. When you weigh the case, you weigh it empty, first. Then you fill it with water and subtract the filled case weight from the empty case. Then you convert the difference in grams to grains and you have the exact maximum case capacity. If you use any other substance, you need to know its average density. Sand won’t have the same density as water, and will require knowing its actual density per cubic centimeter. Water has a 1 to 1 correspondence so it is the basis for doing this. As to having water left in the casing, just re-size it and blow it out with a hair dryer. As Alan says, it takes several hundred degrees of temperature to damage brass. A hair dryer won’t do it. Or you could set it in the sun and let it evaporate that way. And you’re right. If the milspec brass has a significantly smaller over-all volume, it will have higher pressures with the same charge weight and projectile weight, using the same type and brand of primer as a rule.
        Elton P. Green SSG, USA. Inf. (Ret.)

    5. What’s the difference between .308 Winchester and 7.62 x 51 MM NATO cartridges. Chamber pressure and small but interesting dimensional differences. Take a careful look at standard cartridge drawings, paying particular attention to demensional differences.

    6. I’ve recently purchased a Springfield M1A and their included manual states the rifle will fire either .308 or 7.62 as long as it is quality factory ammo manufactured to SAAMI/NATO standards.

      In that case, what are the benefits/trade-offs between the two calibers? Price? Accuracy? Availability? Why should I chose one over the other for my M1A?

      *I’ve purchased the scout/squad variant – I do not intend it be a long range/precision engagement rifle. Moderate range consistency/reliability are my priorities.

      1. Try to stay away from the cheap (especially the steel cased) 7.62, as it is not always within tolerances. If you wish to use surplus, stay with Israeli ROK or US surplus, which will be within NATO specs. It won’t be as accurate as the commercial ammunition. But it will be noticeably cheaper which may make it desirable as practice ammo. Commercial ammo is generally more accurate than the surplus ammunition due to the commercial manufacturers’ closer accuracy requirements. Remember, most milspec ammo is designed to have about a 3″ dispersion from a test barrel at 100 meters, because it is used in machineguns primarily. Most commercial .308 Win. is designed to be fired in civilian rifles and much of it is designed for either competition or hunting. It is held to higher accuracy requirements. It will cost more but it will be noticeably more accurate in your M1A. One other thing. If you shoot surplus ammunition, stay with boxer primed brass. It can be reloaded.

        1. Match Ammunition, if you can find any, was usually quite accurate, though there were lot to lot and rifle to rifle variations. Also, primers were not crimped, saving a bothersome operation for those who reload.

          1. You won’t notice much difference between both rounds. Military 7.62 rounds will probably have a bit more ass to them and hit the target harder. Military 7.62 NATO ammo used to sell for $0.015 per round back in better days. Now it’s 3 times more when you can find it, but still cheaper than commercial ammo. I like my reload for training and play or compition, I’ve got 20 mags loaded with 4 A.P. 1 Traser, the standard military load out except I use A.P. instead of ball ammo. I also keep 5 mags loaded with tracker for nights. This is my load out I’ve used as a Marine, High Risk HIGH Pay Contractor, Police Officer I keep my go to he’ll bag and this load out for both M14 and AR15. How you set up Is what you believe you’re needs will be. Military ammo will be more weather proof and water proof than commercial ammo. This info I’ve passed on to you is something to consider. You’re rifle should work well with any .308 or 7.62 NATO ammo

          2. Firing real Match grade ammo in a service or combat rifle is a waste of money. You won’t notice the difference. Match ammo is designed to be used in a Match rifle. The two together will produce the desired result. Used speratly not so much. From a long time CMP shooting I’ve seen a lot of this with less than satisfactory results

            1. I think that depends on the service rifle. I have both M1s from the CMP and a 1903A3. I have shot match grade ammunition and service grade ammunition in both of them, and group sizes with match grade ammunition tends to be 1/2 or less the size of service grade ammunition. I also have a civilian HK91, which is an original from around 1975. It also likes match grade ammunition much better than service grade, and I shoot both .308 Winchester and 7.62 X 51mm NATO in it. It feeds and cycles all that I’ve fed it except some poorly spec’d surplus I tried years ago. Also, because the delayed blow-back roller-locked action doesn’t start to move until pressures have dropped to lower levels in the chamber, its both soft shooting and doesn’t damage the brass much. I did have to put a pad on the ejection port to keep it from denting brass, though. As long as you keep your pressures reasonable when you reload for it, it doesn’t deform the brass too badly, either.
              Elton P. Green, SSG USA. Inf. (Ret.)

      2. The difference between the .308 Winchester ammunition and the 7.62 × 57mm ammunition is the brass The military round has a thicker case head and have a crimped primer and thicker shoulder and neck. It’s made to survive military combat as well as for both rifle and machine gun use. And is sealed against weather and water damage.As a result the interior of the case has a smaller diameter and will hold less power than a .308 Winchester case. Also keep in mind that 7.62 NATO ammunition is manufactured with both boxer and burdan primers. Some of the military brass can be very brittle or very stiff. Keep in mind that it was meant for a one time use. I only use U.S. military or NATO marked brass, and only to recreate the military ammunition that I won’t be able to pick up again in some action matches. When resizing military brass make sure you rotate it a quarter turn at time with each press in the die. It’s also a pain in the ass to deprime and to decrimp the primer pocket so that the new primer can be incerted. For reloading best to use commercial .308 brass for reloads. The chambers on military barrels have a slight difference in the shoulder and throat. This is to ensure reliable function in hot dirty barrels. As a result it stretches softer commercial brass a bit more. This makes trimming the case neck nessisaery so the reloads will chamber properly. The exterior of both rounds are the same. Commercial ammunition is loaded to higher pressure in some loads, this isn’t a real safety issue but may cause extraction problems. The only real issue is head space of you’re barrel. Commercial barrels tend to have tighter chambers than military barrels. Military barrels are normally crome lined. I’ve used both military and commercial brass for over 30 years in both bolt action and semi auto rifles with no issues. If in doubt fallow the advice of the better reloading books.

        1. Mr. Furbush, you are correct on all counts as far as I can tell, except for the 7.62 typo. And I really dislike Burdan primed brass. The military brass like Lake City was designed for machine guns, so it was made thicker at the casehead and the web. It is designed to withstand being chambered and extracted by bolts and bolt carriers which exert more force than a semi-automatic rifle, and the primer crimp is done for the same reason. No machine gun crew can afford malfunctions due to head separation or failure to extract or a loose primed jamming up the action of his pig in the middle of a serious firefight in a target rich environment. It might let some of the enemy get away. The machine guns our military use are hard on brass so the brass is designed to withstand more abuse than most commercial brass. The thickness of the brass and crimped primer pockets are about the only differences between Lake City brass and commercial brass. I also reload both types of brass for my .308s and my military -06s. I have no issues with either type of brass as long as I stay a couple of grains below the max charges recommended in the manuals and full length resize (two or three times) brass fired in the MGs. I do advise any of you who haven’t been reloading to work up to your accuracy loads carefully when using milspec brass, though. And thank you for your service, both in and out of the military, Mr. Furbush. What branch, if i may so inquire?
          Elton P. Green
          SSG, USA., Inf. (Ret.)

          1. You’re correct good sir typo 7.62X51mm. I’ve noticed a small difference in accuracy in my 03A3 with match 06 ammo. Most M1 and M14 service grade rifles won’t show much with G.I. match rounds. I was a Recon Marine scout sniper. I ended up in STA PLATOON in GW1 The 2 weapons I was issued at the time the M40A1 for day and the M25 with a suppressor and night scope. For night work. I actually preferred the M25 for both. The M40A1 is a fine weapon and I have my own that I built myself. I also have my own M25 built on an LRB forged receiver. I haven’t bothered with a suppressor or night optic, don’t really need them. I also have a HK 91. I’ve used both Argetine FAL and Iranian G3 rifles as a contractor. Never cared much for the AK47. A good combat rifle of course. Just not for me. The M40A1 I used in the Corps was Fed a diet of the match 168gr round as was the M25. The new load uses the 175gr searra match king bullet. I use it in both of my rifles. I only shoot the 150gr searra in both my Fulton Armory .308 and my WW2 Springfield M1 rifle. The heavier bullets aren’t good for the M1 op rod. The 168gr bullet killed very well in combat. I’ve never used the 175gr myself. I’m sure they work. My oldest son used the new M40A3 rifle as a Marine Corps sniper before he was KIA in 05 in Iraq. He told me they were still issuing the 168gr. Most rack grand M1 and M14 rifles I’ve used won’t shoot the match ammo any better than ball. A.P. tends to work a bit better than ball at 600. The heavier bullets account for that I’m sure. Match tuned 03A3, M1, M14, AR15 rifles will always give much better results with match or well assembled hand loads as I’m sure you know. I’d advise the reader’s of this forum not to shoot ball or standard ammo in a Match tuned rifle, it’s unnecessary wear on the rifles. For practice shoot a standard rifle with good quality factory military ball, commercial, or a well assembled hand loads. You can’t go wrong. I’ve had great luck with Portuguese, British RG and German 7.62×51 ball. These rounds give consistent accuracy. The South African 7.62 NATO tends to run hot and cold. I feed it to my HK91 it eats anything I give it and rings the 300yd steel plate all day long.

            1. Sorry to hear about your son, sir. May God grant that you both meet at Jesus’ feet in the time to come. God bless you and yours and deep and abiding thanks for your service and sacrifices. Your fellow soldier:
              Elton P. Green, SSG. USA. Inf., (Ret.)

    7. Dear friends,
      Let me interject some uncommon sense especially if you use your weapon(s) for self or home defense and are ever involved in an shooting incident. I hope for your sake you were using the exact ammunition stamped on the barrel. If not, you are going to jail. You also have a better chance of avoiding jail if you using commercial, non mil spec ammunition and one that is not a reload. Consult your attorney for law specific to your state.

      1. Wtf are you babbling about? Been reading too many gun magazines. Back up this statement with actual case files that show a pattern or stop propagating bullshit.

        1. CH – I can not speak for the comments you responded to, however, from a law enforcement and judicial point of view, the laws can be interpreted in a number of ways (and have been). They can be read loosely or very precisely. It all depends on how far the police and the prosecutors want to push things. Here in California, for example, the Moonbeam Cartel is absolutely anti-gun (except for themselves). We know which way the wind blows if we run afoul of them.

          They will push things for all they are worth if they think they can get away with it; in other words, the defendant can’t afford to fight back. So laws are interpreted in their favor. Not using the ammo specified on the weapon or in the instruction booklet might very well be interpreted as not using the only acceptable ammunition. Now, on the firearm, it gives the caliber. Some ARs, for example, might list 5.56, .223, or both. You can see how Moonbeam and his thugs would decide whether or not you were using acceptable ammo. In the instruction booklet it gets even worse. Many booklets actually name the brand of ammo which the manufacturer recommends based on their testing.

          Just as a police office can stop you and, without making anything up, find violations even if you were driving as perfectly as you could, so, too, can a prosecutor find ways to charge you based on what ammo you use… or didn’t use. Note that I didn’t go into handloads. That’s even more precarious.

          You best believe, what Roy said is definitely NOT BS. That’s based on 21+ years of law enforcement experience. As for me… I use whatever my firearm will handle, based on caliber not brand or special use (military vs civilian), but on what I am using it for (range, hunting, self defense).

          1. I spent 33 in lawenforcement, 7 of them LAPD. I’ve only seen ammo became a factor in one incedent. Prosacuters are overwhelmed with the cases they can win. They won’t file on bullshit like that. I’ve seen them kick back murder 1 cases that should have been just go through the motions. We didn’t have a Priest and 12 nuns for eye whiteness and these animals are back on the street. The only thing they pay attention to is if the gunshot wound(s) were the actual cause of death. You have to have done something that you lied to the investigation team about to get the county attorneys attention. Or shot one of the ” Beautiful People ” to get Jamed up over just you’re ammunition choice. It’s is so that a cop can find 100 ways to fuck with you, I only did that with Ganstas and the more serious juvenile punks. That way when they finally do something serious it’s not a first offense. All pulling that shit on normal citizens will get you is a shit load of cases that the city attorney will kick back If they even get that far as well as a long list of civilian complaints that you don’t need in you’re jacket. One of these times you’ll pull that shit on the wrong citizen and you’re going to find yourself talking to you’re division chief because you wrote up one of the superior court judges girlfriends. Good luck to you with that one, you’ll find an I.A. head hunter looking at you forever if you last that long

        2. Don’t be a wise ass CH. This man knows what he’s talking about. Do your on research. I’m a retired litagation claims specialist.

      2. BULLSHIT!!! What law school did you not graduate from? The only reason you need to make sure you use the ammunition recommended by the manufacturer is so the weapon doesn’t blow up and kill you. Any ammunition even you’re own reloads is acceptable. The use of reloaded ammunition only voids you’re warrinty. It doesn’t violate any laws

      3. What law school did you not graduate from? What exactly makes you qualified to give legal advice? Guys like you are foolish. You read these fairy tales in gun rags and the internet written by wanna be combat instructors that try to pass their BULLSHIT as actual training.

      4. Sir, your comments are appreciated and probably accurate where self defense is concerned if you live in New York, California, Maryland or the state of Massachusetts, or some of the other Peoples’ Democratic States, but I personally don’t carry or use M1s or M14s or M1as for self defense. They just don’t fit in a holster well, they are hard to conceal, and you get funny looks when you carry them down the street. For the house, i use a revolver, a semi-auto pistol, a shotgun or a lever action rifle in .44 Magnum, loaded with .44 Specials. That way I don’t shoot through the assailant, all the walls of my house and two or three neighbors’ houses. Assault rifles and full-power combat rifles such as the AR15 and the M1A or HK91 (also the AK and SKS variants) are good CQB weapons, assault weapons, in some cases long and medium range weapons and hunting arms, but they are primarily designed as offensive weapons, and are of limited use in nearly all self defense situations. Thus the type of ammunition used for self defense in these weapons isn’t at issue here. What is at issue is what will reliably function in the rifle. Also, Mr. Furbish is completely correct in both his statements on this subject. Check with U.S. Law Shield for answers about this.

    8. Blimey fellas. I cannot disagree that ordinarilly you should shoot what the rifle is made for if you are using factory ammo, but surely IF you are developing a load for hand loading you simply check your FL resized cases are to spec and work up a safe load depending on the manufacturers data. I have not read all of the comments on here so if I am repeating anyones comments, I apologize, however, I have not seen tight bore mentioned. Way back when in the UK, the NRA used to issue 7.62 NATO ammo for some competitions. Much of this ammo had a bullet of .306+/_ rather than .308, so the target rifles of the day often had “tight” bores to make the most of this slight reduction in calibre. Now, IF you stuck a .308Win factory spec round up one of these you may well be picking bits of bolt out of your face, but they dont make them like that anymore. Plenty still about though. Personally I would probably use .308 (or better still Lapua .308 small primer) brass and develop a load to suit whatever I was shooting. Cheaper, more consistant, and possibly safer…Brits eh? Enjoy your shooting folks, whatever it is.

      1. Some target rifles were done that way here, too. Two thousandths of an inch shouldn’t appreciably increase pressures as long as the bullet isn’t contacting the lands to begin with, but it might, and the bullet diameter you show is an example of how ammunition made by many of the other NATO countries was made out of spec. originally. That’s why the chambers on battle rifles and machine guns are made with slightly greater head space and SLIGHTLY larger chambers than commercial rifles (with the exception of precision or sniper rifles). But all American and German rifles will still pass SAMMI Go/NoGo guage tests. British and Israeli rifles will, too. If its from South America (other than Argentina or Brazil) and military, or from India, you would be wise to have a gunsmith guage the barrel to determine if it is safe to shoot with any ammunition. And all BM59/62 Italian rifles need to be checked, too. Some of them have head space problems.

      2. I’ve seen tight chambers cause extraction problems, but I’ve only seen the issue of tight bores in the difference between Russian and Finnish mosin nagant rifles. The Russian rifles have .310 – 311 bores. Some of the Finnish rifles have .308 bores. They got hot after just a few rounds. Non ever blew up that I ever heard of or used. The Finns switched to the .311 size bore to slove the problem. They made use of all the captured rifles and ammo

        1. Jack, Europe is a tad different, as I’m sure you know. An example of different bores for the same cartridge that I remember from being over there is the 8X57 Mauser, which in some of its earlier versions had a bore of .318, and then went to .323 bore size. Generally, you only see this in some of the m1895 or older mausers, but it is there. Also, a modern example is the first few production runs of the Mini 14 in 7.62X39, which had a .308 diameter bore. They still shot the Russian ammo just fine, though.
          Elton P. Green, SSG USA., Inf. (Ret.)

          1. Your correct about Europe. I’ve only used a German G3
            Brit. L1A1. The only target rifle I’ve ever used is the Envoy. A fine rifle. I’ve owned several Enfield #3 & #4 rifles. No issues there. I own a Gee 98 made in 1899. It has a 318 bore. I have to shoot my loads in it. The rest of my Mausers are. 323. I remember the issue with the early Mini 14. The had extraction problems because of over chamber pressure. I’m not sure how they corrected this

            1. Mr. Furbush, I think that Ruger changed the bore diameter to .310 or .311. I do know that the problem was corrected.
              Elton P. Green SSG USA, Inf. (Ret.)

    9. Several ammunition manufacturers have ammo marked 308/7.62×51. Apparently they need to be corrected by Gregory, according to him, you can’t do that. I have read this thread over and found nowhere where he shows any researched facts and figures. Guess if you belong to a range and can shoot makes you know all and can disrespect and insult anyone who has a legitimate question. Glad he is not at my range. All I see is Gregory being an ass.

      1. WTF are you talking about? Who was there you or him? In 45 years of competition shooting I’ve seen a lot of things that ain’t supposed to be so but the are so. I’ve never personally seen this situation, but European target rifles are different in many ways from US rifles. I’ve shot thousands of R.D. Green British 7.62 NATO ammo. It used to be around and cheep just like Portuguese 7.62. Both shoot well and are very consistent. Pulling a few rounds of each apart there was very little difference between loads. I wouldn’t call it match ammo but it’s good stuff and will hold the black at 600

    10. I just bought a PSA PA-10 and it says 308 on the barrel. That’s great except I reload and I buy once fired 7.62×51 brass that has been cleaned, resized, and primmer pockets reamed. I’m assuming that reloading them to 308 spec’s should work?

      1. On January 28, 1986, the NASA shuttle orbiter mission STS-51-L and the tenth flight of Space Shuttle Challenger broke apart 73 seconds into its flight, killing all seven crew members.

        I’m relation, that space shuttle, “should have worked”? Then again if you want to buy a brand new Mercedes then run to Wal-Mart and swap out the tires, for whatever I’m-godly reason? Have at it! Personally? I would rather spend the extra 12 cents per round that you might be saving and buy factory fresh ammo. But hey? I’m funny that way!

      2. After sizing the brass, the 7.62 will still have thicker walls, meaning less space for powder to expand, meaning potentially greater pressures. Unless you have the tools and safety equipment necessary for measuring pressure, I’d recommend using the ammo marked on the barrel.

        1. In reloading military brass, which is thicker walled than commercial brass, use the Starting Load in whichever manual you fancy, and work up SLOWLY from there, say 0.5 grain increments..

      3. Ignore Mr. Romeu. The answer is yes. But remember to stay on the low side and work up. The brass is thicker so pressures rise a little quicker. Your rifle is rated for 62,000 PSI. Stay at about 56,000 PSI or 47,000 CUP and you’re all right when using the .308 data. Start about 10% below the maximum load in the load manual and work up. Check your brass for signs of scuffing on the face, and primer flattening. Measure each of your test cases with a caliper and compare them with once fired commercial brass. Work up in half grain intervals using 10 rounds for each load. Use commercial brass fired only in your rifle for the comparison. The brass has exactly the same outside diameter and dimensions as the .308 Winchester, and re-sizes to exactly the same dimensions.
        I would caution you to run it through a small base die or a full length resizing die just to make sure it will chamber, as it was probably fired in an M240 mg, but that’s about all you need to do to use the brass. The M 240 causes the brass to stretch slightly due to the rapid cyclic rate of fire, which most gunners set at around 900 rounds per minute because the lower cyclic rates let the gas port carbon up, jamming the gun. But all semi-auto and automatic rifles stretch brass somewhat due to the fact that chamber pressure is still present during ejection. That includes civilian and military semi-or automatic weapons. I use the US 7.62 in several rifles. The thing to remember is that even if the brass is out of spec, the full-length die will bring it back into proper specs. And you need to full length resize if you’re going to use .308 / 7.62 in several rifles. Also, try to stay with US brass. The make-up of the metal will be within safe specs for your rifle. German brass, Sellier % Belou, IMI, and Privi-Partizan brass is ok, too. When your tests are complete, stay with the brass you used in the test and you will be as safe as with commercial loads. Use once-fired brass only for each 10 rounds, and make sure all rounds have the same headstamp. If you change brass or mix brass brands, pressures will be different and inconsistent. Loading 40 to 50 rounds should do you.
        Stay with the same powder bullet type/weight and primer brand throughout the test, too, as changing any of these components will change the pressure curve. Once you have a baseline for pressure and accuracy for one brand of brass, you can then do the same for other brass or components, but by going about 1 grain of powder down from your original load data and working up. Same for changing other components. If you follow these steps, not only can you use the brass safely, but the Lake City brass and the IMI brass will produce some of the most accurate ammunition you can fire.
        Now for my credentials: I am retired US Army Infantry. I was a sniper on the DMZ in 1988 (ROK), I was an armorer in the 25th Infantry for three years. I have shot expert with All the weapons the army had during my active duty. I trained soldiers in rifle marksmanship, basic and advanced, pistol marksmanship (m-9 and 1911A1) basic and advanced, M249, M60, M240 A/B/C, M2 Cal 50 HB Browning MG basic and advanced, conducted range maintenance and 2nd level armorer’s maintenance on all of these weapons, cleared and repaired their malfunctions in the field, and repaired them when parts were available in the unit arms rooms. I’ve also repaired and rebuilt the 25mm chain gun feed and bolt mechanisms on the M2 Bradley Fighting Vehicle. I am also an avid reloader, and have been reloading since I was 14 years old. I started reloading for my Dad’s 30-06 around 1965. I currently reload for the 223/5.56, 6mm Remington, 25-06, 270 Win., 308/7.62×51, 30-06, .300 Winchester Magnum, .35 Whelen, 45-70 Govt., 357 mag/38 special, 44 special/44Mag, 45APC and 50/90 Sharps. The new Lee manual, the new Speer manual, and the new Lyman manual will give you good guidance for working up loads. The Hodgdon manual will give you recipes for Hodgden, IMR and Winchester powders for about everything you will want to reload. Get them and read/follow the instructions. They will keep you reloading safely. Have fun, shoot straight and stay safe. Hope this helps.
        Elton P. Green SSG, USA, INF. Ret.

        1. Elton P Green, thank you for replies and your service. Helping us who have legitimate questions in a respectful and professional manner is much appreciated.

          1. I hope this did help you. If you get a Speer or Lee reloading manual, either one (Both is a good idea) will give you step by step instructions for working up safe loads. And you’re welcome. I’d serve again tomorrow if they’d let me.

            1. Thank you for your valuable advice. I appreciate your respectful and kind reply as well. Reading your kind of comments is one way for others to learn rather than be frustrated and turned away having learned nothing. Additionally, I thank you for your service to our country, sir.

            2. I found Lyman manuals useful too. As a general comment, whichever manual or manuals strike your fancy, spend some time reading them BEFORE actually reloading. By the way, I used once fired LC Match Brass picked up at Quantico. No fired brass left on the firing lines. Fired brass went into cans behind the firing line, or into whatever bag or container civilian shooters like myself brought. I never found the use of small base dies necessary. As by then, I was shooting bolt action rifles, Match Brass that had been fired once in Match Grade M-14’s used by Marine shooters seemed to last virtually forever. Lest I forget, the service of people such as yourself is not forgotten, at least not by old goats like myself.

            3. Alan, Lyman loading manuals are very good. One of the things I like about them is that they aren’t proprietary because Lyman doesn’t produce either the powders or the bullets used. I currently use their cast bullet reloading manual.
              SSG Elton P. Green USA Inf. (ret.)

          1. Yes, but not accurately.
            I have an older savage 110 in 308.
            The bolt is tighter with certain rounds, and fine with others. (Same batch, Norinco 7.62×51)
            My savage was very picky with ammo to get MOA accuracy. Only one so far is Barnes TTSX 168. With the Norinco ammo, it fires safely, had one split neck out of 100 rounds. But asides from controlling trigger flinch, it isn’t much use. At 100 yards, I can barely hit a 14″ target. I am going to try brass Mil Surp from Austria this weekend. But considering all millsurp is lighter projectiles, I have my doubts on accuracy for a rifle that prefers 165 to 168 grain. (Even Remington 308 rounds at 150 and 180 grain were all over the place btw)

            Elton, Quick question…
            Considering the 7.62 has slightly less pressures, but often also has lighter projectiles, is there a rough correlation?

            Ie: 7.62×51 147grain ~= 308 168 grain (For accuracy and trajectory?)

            Sounds like a definite maybe, not always, but sometimes kind of question.
            I’m always right 50% of the time…

            1. The quick answer to that is no. The 147 grain boat tail has a much lower Ballistic Coefficient. As a result, it has a poorer trajectory at distance. The 165 grain boat tail has a much higher B.C. and the 167 and 168 grain match bullets have B.C.’s in the range of .480 or so. Trajectory at distance is much flatter. More importantly, wind drift is noticeably less. What the match grade round loses in initial velocity it gains in retained velocity down-range. Accuracy is another issue, but it depends on the manufacturer, lot # of the ammunition, and whether the rifle likes it. Most NATO 7.62X51 only has to shoot a 2 1/2 to 3 inch group from a test barrel, since it is generally used in machine guns, and pin point accuracy isn’t required. Only the match grade 7.62 is required to shoot tiny groups from a test barrel, so most match grade .308 Win or 7.62X51 ammunition with match projectiles will be far and away more accurate than nearly any mil-spec ammunition. Also, most of the Norinco ammunition won’t shoot accurately in anything. And the Russian stuff isn’t much better. As an aside, I have a Savage model 10 with a synthetic stock, and its pretty picky, too. But part of the problem is that the synthetic stock is flimsy and if it is rested too near the end of the forearm, it sometimes touches the barrel, which interferes with accuracy. I’m going to get it glassed to stiffen it as soon as I get the money. But you might try hand loading your rounds. RL 15 and IMR 4350 give me very good accuracy with 180 grain Sierra Pro-hunters and Gamekings. Also, if your stock is synthetic, rest it near the action (maybe directly under the magazine) and not on the fore end. That will let the barrel vibrate freely with each shot. See if it improves and let me know.

            2. I’m going to correct part of my April 12, 2018 answer. The answer is actually yes and no (but more no than yes). At ranges out to about 500 yards (more or less) the 147 grain round will have a fairly close trajectory to the .308 Win. match 168 grain ammunition. Accuracy will be notably poorer as noted in the original comment, unless you get a lot number that was manufactured to closer tolerances, which can happen. For instance, when a sniper didn’t have Lake City Match ammo, he was instructed by the manual to test various lots of ammunition and use the most accurate. After 500 yards or so, however, the poor ballistic co-efficient or the 147 grain bullet causes it to differ in drop and wind drift at an increasing rate. Also, the different rounds probably will require different initial zeros at 100 meters due to differences in initial muzzle velocity. Using the same zero, I would expect one round to impact the target at 100 yards higher than the other. My experience dictates that the heavier projectile should impact higher due to it having more time in the barrel and allowing recoil to have a slightly greater vertical effect as it exits the barrel. But again, different lots of ammunition can have different results, so yes, it is a definite maybe type of answer, except its more of a mostly that way answer, with some exceptions due to variations in 7.62X51 manufacturers. And I hope this correction to my original answer is somewhat clearer than mud.
              SSG Elton P. Green, USA. Inf. (Ret.)

          2. Yup. Bolt guns will run with any safe load as long as you’re rifle doesn’t have head space issues. If you’re using new brass you only have to neck size it. It will fire form to the rifles chamber. Of you want to use once fired military brass you’ll need to fill length resize it for the first load and neck size for the rest. You’ll probably get 10 to 12 loads out of each case. I’ve actually gotten more

      4. You’re fine with military brass. It’s a bit more work but often can be had at cheeper price. The exterior dimensions are the same. You’ll find the military brass won’t hold as much powder because the brass is thicker. This makes the interior smaller. It’s not really an issue unless you’re trying to get a maximum load of some type. Make sure you resize you’re brass properly. A little extra case lube a run it through the die 4 times turing it a quarter turn each time if you’re using it in a gas gun. In a bolt gun it’s not that much of an issue. Only use US military or NATO marked cases. I’ve been loading them for 30 years, never had an issue. I like using 7.62 military brass if I’m shooting an action match and can’t recover my brass. It’s cheap and easy to find

      5. Unlike some here, I will actually answer your (very reasonable) question. Yes, they will work. The external dimensions of the brass are EXACTLY the same as .308 Winchester. As a matter of fact, Winchester copied the round so that they could introduce it as a commercial round. The differences are in the case wall thickness and the case web thickness at the case head. Because the brass is thicker it has a quicker pressure curve, though. You need to start at least 3 grains under the maximum charge for a .308 Winchester load and work up from there. Because it is military brass, it is stronger (has to be to withstand use in machine guns) but it has a little less powder capacity, and as a result, pressure peaks more quickly. Also, when you resize this brass, use a small base die if you’re going to shoot it in a gas gun. The only reason to avoid 7.62X51 ammunition in a rifle chambered for .308 Win. is if the ammunition itself is out of specifications, which does happen with some of the NATO countries. If you hand chamber the brass and the bolt locks up properly, the brass has been sized correctly and will be fine. I use both .308 Winchester and 7.62×51 in all three of my .308 rifles, including my HK91. And by the way, not all milspec brass is equal. If you change brands you need to start working up your loads all over again. My WCC brass is more sensitive to pressure than my LC brass, for example. What is a safe load in one isn’t necessarily safe in the other. Also, to show that the two rounds are interchangeable, the US Army uses both 7.62X51 Lake City Match and Federal Gold Medal Match in the M24, the M2010 in its 7.62X51 chambering, and in the M21 or the Squad Marksman version of the M14 rifle. Bullet weights also vary in all these cartridges, from 168 grain match boattails to 175 grain match boattails. Both loads cycle beautifully through the gas guns and are highly accurate in the M24 out to about 1000 yards. Again, remember to start at the menimum starting load as listed in your reloading book, and work up.
        Elton P. Green SSG, USA, Inf. (Ret.)

      6. Again, I’ll answer your question instead of implying you are an idiot, which you are not. I also reload military once-fired brass. If its been resized to .308 Win dimensions, it should be fine. (308 Win, and US 7.62X51 have exactly the same outside dimensions, as Winchester just copied the military round.) Just chamber some empty brass in your rifle first. This will tell you if it fits the chamber because if the bolt will lock up, its sized correctly. Then reload it normally, working up from an 85% charge of your favorite powder, projectile and primer, 5 or 10 rounds at a time, until either you are satisfied with accuracy and velocity or you begin to see flattened primers or head scuffing. If you see this, back down about one grain. That’s a safe load for your rifle. If you change any component, you’ll need to do this all over again. The alternate thing you can do is run each piece of brass through a resizing die just to be sure. Then chamber it in your rifle. Again if it locks up with a minimum of force, it will be fine. Just remember that the mil-spec brass is thicker and loads reach peak pressures with lower charges. Also, don’t use ANY magnum primers because they will only create pressure problems. And make sure your primers are completely seated. If they aren’t, you will get an out of battery fire. If you are using a semi, you might think about using mil-spec primers in the reloads, also.
        Elton P. Green SSG, USA., Inf. (Ret.)

    11. No, Greg does not live overseas. He belongs to a rifle club and knows what he’s talking about, and also, he is an excellent marksman ‼️

    12. Gregory was very helpful on providing you all on some facts and figures that took some time to research. I appreciate the time and effort it took. There is always gonna be several out there that do not agree on your views and research, Why i dont know, like viper said use the ammo that is recommended for that weapon and be safe brothers. army vet.

    13. Gregory Romeu, you seem to be a “internet troll” that pounces on anyone and anything that can make you feel smart in your own eyes, I’m here to help you, you are being a jerk, your life is missing something don’t sit at home and worship yourself. Back away from the computer and go look in the mirror. We hate your attitude here. Please try to educate yourself in basic kindness, maybe read the Bible. We would gladly welcome you if you would try to be a bit nicer. You do have a good heart inside you, feed it please. People will respect you.
      Sincerely Your friend,

      1. Obviously you have no understanding or idea as to what a TROLL actually is? Me? Not are troll by any means, I just loathe ignorance and stupidity, especially when the ANSWERS are bore right into the barrels of the firearms these people are in posession of. If you took the time to read deep into the text of those I responded to you would find most should not possess a firearm.

        There is no place for niceties once a trigger is pulled. And you with a name like, “Cracker”?

    14. “LONG 7.62 RARE”? Depends on the source! ESPECIALLY when buying milsurp ammo. I recently bought close to 500rds of belt pieces from a guy that bought them at an auction that I disintegrated by hand and I’m averaging about 30% that’s too long for my magazine.

      Sometimes “military surplus” is code for “military JUNK”!

      I should’ve known better because I have inside knowledge! For about a year I was assigned a post as Assistant Barracks Mgr. Anytime we had worn out or just plain UNSERVICEABLE furniture it was sent to DRMO (Defense Reutilization and Marketing Office). They scrap or resell that stuff to the highest bidder. If someone bids $500 for 10,000 rounds of reject ammo and that’s the highest bid, there ya go!

    15. Good read but one big mistake. All else being equal a thicker case will have higher pressure. Less volume and the same amount of powder equals higher pressure.

      1. Buy wouldn’t a 308 case with a heavier bullet, with more powder to achieve longer and more effective ballistic performance generate higher pressures?

    16. Good read but there’s a critical mistake. All else being the same, a thicker case will generate a higher pressure. A smaller volume with the equal amount of powder equals higher pressure. Is a standard .308 a compressed load? That would depend on the powder density and I’m sure all .308 are not compressed.
      From Berger on COAL and Bullet seating depth. “The primary effect of loading a cartridge long is that it leaves more internal volume inside the cartridge. This extra internal volume has a well-known effect; for a given powder charge, there will be less pressure and less velocity produced because of the extra empty space.”
      The converse is true as well “less volume, same powder, equal higher pressure.” Again this assumes non-compressed loads.

      1. The only thing I can say is that you may be overlooking quite a bit in that little phrase “all else being the same”. Most hand loading data from Hornady, Nosler, and Winchester state that there are two different sets of loads, one for .308 and one for 7.62, and the reason given is the lesser room inside the 7.62. There is no doubt at all that 7.62 is done to a slightly lower pressure. It is not “same powder”.

        1. You didn’t read what I wrote, I know 7.62 and .308 are different in nearly the same way as .223 and 5.56 are, except 5.56 is the one with higher pressure. Quote from article “Thicker walls combined with similar exterior dimensions means less powder capacity and a lower “top end” and all else the same, lower pressure and velocity.” This is incorrect, misleading and possibly dangerous.
          A smaller case all else being the same, i.e. a .308 load in a Lake City 7.62 case vs. a .308 case, with the same bullet, same weight and type of powder, same primer the thicker 7.62 case will result in less volume and higher pressure and velocity. This is a scientific fact based on Boyle’s Law. Bullet seating depth will affect pressure as well, seated deeper equal less case volume and more pressure and velocity.

          1. Well, you are entirely entitled to your understanding of my reply. But I quoted you. My statement is concerned with your insistence that you would use the same powder charge on the 7.62 as you would .308. IF you did this, the pressure would be higher, yes. BUT loading specs from Hornady and the like state NOT to do this.

      2. Mr. Lando is correct. If you are using the same powder in both casings (ie: Nosler 308 Win. and Lake City Match, for example) the Lake City brass will have a higher mean pressure when charged with the same type and amount of powder as the Nosler commercial casing. Also, this is true whether the load is compressed or if there is some space inside the cartridge. Also, some of the powders used in military (US) 7.62 are: IMR 4895, IMR 3031, Winchester 748, H4895 and currently, IMR4064. This is just a list of a few of the powders used and being used. Burn rates of these powders are very similar, and most of them will fill the casing to around a 90% or more fill depending on the weight/shape of the projectile. He is also correct about the effect of loading the bullet further out in the neck on pressure. Given the same brand of casing, the casing with the bullet loaded out will have a lower initial pressure, given the same type and charge of powder and the same primer.
        Elton P. Green, SSG, USA. Inf. (Ret.)
        Elton P. Green SSG USA INF

    17. Windham Weaponry SRC R16SFST-308
      Semi Automatic Rifle
      .308 Winchester and Accepts 7.62mm NATO
      16.5″ Medium Profile Barrel
      4150m Chrome Moly Vanadium 11595E Steel Barrel
      I am looking at this rifle..you will note it says it will accept 7.62 NATO ammo is it safe to fire it then.
      From the article a bove you seem to say so. Being that I have served and can get NATO 7.62 I would like a definite answer, if you please

      1. Tim, 1) A blind monkey smoking a crack-pipe can get 7.62 NATO ammo. 2) If you served, in WHAT did you serve? And if so, then WHY didn’t teach you to put into the weapon that which is marked on the weapon? You wouldn’t put a,5.56 ball round in that chamber, would you? In other words, if it SAYS “7.62 NATO” on the barrel, then OBVIOUSLY you would use, “7.62 NATO” ammo.

        Now, go ahead and explain to us all the special privledges YOU have in getting 7.62 NATO ammo, just because you served?

        1. @Gregory Romeu
          Jesus, you are a DICK!!!!! Tim was just asking a question. No reason to be a spiteful prick about it!!!
          It’s people like YOU that are ruining the world for the “good people”!!!!

        2. Gregory… Perhaps he is not in the US? Maybe he lives in the EU or somewhere else where firearms and ammo are severely restricted… Every think about that possibility genius?

        3. Gregory.
          let me ask you a question.
          i have a FN/FAL in 7.62 nato and that’s what i shoot in it.
          but i also have a Savage Model 99 that says 308 caliber.
          so i’m assuming i wouldn’t be able to shoot the 7.62 in my Savage due to the chamber not being as long as my FN/FAL.
          is this right?
          and thanks for any answer.
          and i served as a Marine from 1960 to 1971.
          and yes, a Vietnam vet.

          1. James, Mr. Furbush is correct. Your Savage 99 will shoot either round, as long as the 7.62X51 NATO is of good manufacture. A check for this is to chamber the 7.62 round. Since your rifle is not a semi-automatic, you can perform a function check and if the round chambers and the action locks up properly, it will shoot the ammunition. And thank you for your service, sir. I am glad you got out alive. May God Bless you for a job well done.
            SSG Elton P. Green, US Army Infantry, (Ret.)

      2. The only definitive answer is to have a professional gunsmith determine the exact head space of the rifle. As mentioned in the article, a rifle that is chambered for .308 tends to have a headspace that is tighter, and here you want to think smaller. A rifle that has been chambered for 7.62 USUALLY has a longer headspace due to the multitude of different factories making this ammo around the world. The 7.62 NATO round has a thicker wall and is made to have a lower pressure. .308 is made with a thinner wall and higher pressure. So, sometimes when you use .308 in a 7.62 rifle, the added headspace, higher pressure and thinner wall can make the brass expand and deform in the chamber, and sticking and jamming has been reported. With me so far? SOMETIMES the 7.62 has been chambered small enough that a typical .308 round will not float around at all.

        Now, why is this? It’s all about history. Think back to when this round (7.62) was developed. There’s a requirement for this round that isn’t talked about much but played a significant role in the wall thickness and the longer head space. The round had to be acceptable for full automatic machine guns. The higher pressure was unwelcome as it would affect recoil (think of the out-of-control climbing that ruins the effectiveness of small arms machine-guns). It also affected rate of fire and barrel heating up. So, the less pressure, the slower rate of climb, the less wear and tear, and the ease of using differently sourced rounds. The M-14 was the original recipient of this and later the M-60. I’m not certain but I believe there was an attempt to convert the M1919 over to this, but I could be wrong. If so, please don’t tell my son. Or my wife, for that matter.

        So, we still have military reasons for keeping the 7.62 round as-is in the form of modern full auto arms. Get the headspace checked against go-no-go for both rounds. Pay a gunsmith to do this as he or she (there you go, Hillary!) should have these tools. Though simple to use, fairly expensive for something you may use only once unless you’re a serious hand loader.

        The makers of the rifle you have a question on seem to be saying that the headspace on that rifle is a bit longer than usual for a .308. If so, you might maybe be trading a bit of accuracy just to have that flexibility of using either round. I don’t get the point here, as .308 comes in any sort of configuration and price break you could think of. Your “cheap” rounds of 7.62 might cost you down the road in terms of accuracy.

        1. TheFixer is correct as to the information on the 7.62X51 NATO round. He is also correct about getting your rifle’s headspace checked. If the rifle is headspaced correctly, and the ammunition is within Army Ordinance specifications, you can shoot it in the rifle. A way to check the ammunition for proper specs is to hand-chamber it in your rifle and check to see that the bolt has gone completely into battery. If it has. the round should be safe to fire. But you have an expensive rifle. I wouldn’t use cheap surplus ammo in it just because it will work better with the good stuff.
          On a different note, Mr. The Fixer, yes the M1919 saw conversion to 7.62 by the Army, the Navy and by other NATO countries who received it from us as surplus. Also, the Israelis converted a number of them to the 7.62X51 complete with bipods, quick-change barrels and butt-stocks. Rate of fire was about 550-600 rpm and they were converted to use the same disintegrating link belt as the M60. So you’re right but I won’t tell your wife or son if you won’t tell mine.
          Elton P. Green SSG, USA., Inf. (Ret.)

      3. Tim, from one vet to another, yes you can use both. The rounds are supposed to be interchangeable. You will want to be careful with the country the ammunition comes from, though. Some countries have poor to no quality control, thus their ammunition is not made to Nato specs. Stay with IMI or Western European ammunition, notably British, German, Austrian Polish and Belgian surplus. These countries have good quality control procedures in place. Don’t buy anything loaded before about 1980. Also, check it to ensure it will chamber properly in your rifle. If it won’t, break it down, dump the powder and primer, and re-size the brass if it is boxer primed. At least you will get a supply of brass. If it won’t chamber and it is berdan primed, you’ll just have to toss it. Most of the German brass is boxer primed. So is IMI (Israli Military Industries) and PPU or S$B brass. British 7.62 is almost always Berdan primed. What branch were you in? I was Army Infantry for 20 years.
        Elton P. Green SSG USA INF. Ret.

    18. Myself, I would be wary of using spent .308 brass for reloading purposes unless I knew exactly what rifle it had been fired through prior to ending up on the range floor. The stretch of .308 brass fired through unknown 7.62×51 chambers could result in empties that -might- head separate without warning due to the “headspace stretch” -ALL- occurring at the base end of the case and NOT at the shoulder/body length area (which would happen in carefully fireformed brass).
      All those reloading articles explaining when to discard rifle cases due to the displacement of brass from the base area of a casing (due to thinning) could provide pertinent information about this phenomena.
      I learned to pay this circumstance closer attention when I became interested in reloading for my Rolling Block rifle (and some of my Mausers) that are marked 7mm for use in Latin America during the late 19th and early 20th centuries.

    19. I’ve read lots of articles on this subject. And I like to ask the same question and see how many different answers I get from each article. OK here it goes-I have an M1A loaded with .308NM (National Match) stamped on the barrel. So what can I shoot? Some people say of course you can use both and some people say .308 is too hard on the auto loading mechanism, it’s strictly for bolt action. Some people say since it’s stamped .308 on the barrel it’s chambered for .308 and that ammo works better in that rifle. Now I’ve only run maybe 30-40 rounds of .308 through but I’m wondering if I should start buying the 7.62 NATO. I’ve spent more than a little money on this gun and I sure don’t want to cause me or the rifle any damage. All I want is the facts ma’am.

      1. The simple answer here is that the BARREL is marked .308NM. It means that the barrel has been made to a certain degree of accuracy. It does NOT mean that you can or should change calibers to the 7.62 NATO. It’s still a .308, man. You really want to jam 7.62 into what must be a fairly expensive barrel to start? Even if you get the round to cycle, please think of what you are doing to the chambering. M1A NM means that has been set up for .308 target shooting or sniper activity. If you have an M1A that has been chambered for the .308, you (or someone) had to change a few of the 30-06 gas piston components, not to mention the stock itself. So, your argument that the rifle can’t handle the round is senseless. And in a rifle that was originally set up to handle the 30-06? After how many rounds do you imagine this failure to take place?

        1. WYF Is your problem? Military weapons issued to troops in military service are fed issue ammunition. The military caliber is marked on the barrel so the correct ammunition is issued and loaded into the weapon. Shooting 5.56mm rounds in an AR15 rifle will do no harm to that rifle provided it was assembled correctly. I’ve been doing this for a long time with both factory and rifles I’ve put together out of military spec. Parts. Same thing with 7.62 NATO and .308 Winchester. The simple difference is military brass is thicker so less room inside the case. The exterior dimensions are the same. Military weapons are fed military ammo only while in military service because that’s what’s issued. They will function just fine with commercial ammunition. Same is normally true in reverse.

      2. Ignore Mr. Romeu. If it says it will accept both, it will accept both. If you are really concerned, call Windham Weaponry and confirm. And thank you for your service.
        Elton Green, SSG, USA Inf., Ret.

      3. The NM barrel for the M1A has a match chamber, which is on the tight side of the chamber tolerance for the .308 Win. cartridge. It will fire 7.62X51 safely if it can chamber the ammunition. In other words, if the ammunition is within US Military Ordinance Department specifications. If you buy surplus ammunition, check it to insure it will chamber properly. If the bolt won’t lock up, the ammo is out of spec. Disassemble it and re-size the brass for reloading. If it will chamber properly, it will be safe to fire. Again, the two cartridges have EXACTLY the same external dimensions with the only difference being case thickness being greater in the military version and the pressure average being 4,000 psi lower in the military cartridge. Stay away from the Italian, Russian and Spanish stuff. Also, stay away from any South American surplus. Poor quality control with these countries means you don’t know what you’re getting. Israli, German, Polish, South Korean, Greek (mostly) and US surplus ammo is pretty reliable. I’m shooting Greek 30-06 in my CMP M1 Garand.

      4. Hey JD you’re rifle is a fine target rifle. You’re best results will be with commercial .308 Winchester ammunition. You’re rate if rifling twist is 1:10. This will stabilize up to 175 grain match bullets very well. You can also shoot 150 grain loads for the shorter range matches. Out to 200 yds. They work well. The 175gr. Load works best at 500 and 600 yards. It goes to sleep at around 350 yards and is still over 1000 fps at 800 yds. This is why the Marine Corps and the Army switched back from the 168gr. Bullet. The 168gr was the favorite at 2 and 300 yds and bucked the wind well out to 600. Being the maximum range in service matches the military wanted to settle on one bullet for all long range work. That work well but not as well as the slightly heavier bullet. You will get you’re best results with factory match ammo or a carefully made hand load with commercial brass. You can safely fire 7.62 NATO ammunition but you my have extraction issues due to you’re tighter chamber specks.

      5. A National Match M1A is an M1A designed from the ground up for accuracy. It has a precision trigger, precision sights, national match bolt, operating rod, gas system, barrel and flash suppressor. The chamber and barrel are bored and rifled to very close tolerances, the barrel is generally gaged to be within around .0005 from breech to bore, and the stock and hand guard are hand fitted to exacting tolerances to insure proper bedding of the action and barrel. The NM designation is the proof that all this has been done to the rifle and that the rifle should meet accuracy guarantees with match grade ammunition. However, the NM designation has nothing to do with the cartridge the rifle fires. Also, the Springfield Armory has designed their M1A to operate within the higher pressure limits of the .308 Winchester ammunition. It is specifically designed to shoot any properly manufactured .308 Winchester ammunition with bullets up to 200 grains without harm to the rifle. It will also shoot any 7.62 X 51 NATO ammunition which has been manufactured to be within Ordinance Department specifications. The last four words there are important, as some of the surplus ammunition produced by other countries are definitely not within tolerances as laid out by the US military ordinance departments. Any US, German, British, Israeli, or Eastern European .308 is ok. Same for these countries in 7.62X51. Add South Korea to that, too. Just do a hand chambering of the 7.62 to insure it isn’t out of spec in respect to overall length. But if you’re looking for accuracy, stay with the .308 Win. National Match ammunition. It’s designed for match accuracy and long range shooting. But don’t believe me. Call Springfield and get their answer. They made the rifle and they will tell you what it can and can’t shoot (They’ll also tell you that reloads void the warranty). Good question, though. I bet you get all kinds of answers on this.
        Elton P. Green SSG USA. Inf. (Ret.)

    20. I made the mistake of shooting 308 commercial brass which I reload in my m14
      I have a R.E.M. 7600 in 308 so I used same loads in both
      The m14 ripped apart the brass from long head space blew the mag out of rifle through the shooting bench, the stock split up to my cheek I thought my fingers were gone I couldn’t feel them and was afraid to look if my rifle hadn’t been a military rifle I’m sure I would have been killed all the pressure went down and not back into my face
      Stick with the right ammo for the Gun you are shooting

      1. I had the very same experience with a Mosin M1A when the round jambed in the chamber when and the bolt slammed home, blowing up the round, cracking the stock and peppering me with mini specs of blood all over my arms, but I didn’t find any cuts on me? Luckily, I sold the busted up rifle at a gun show for a grand!?! THAT was even more amazing???

      2. Who made your M14/M1a? I’m curious as to the manufacturer because it sounds like it may have been improperly head-spaced. This might not have been due to your loads.

    21. Have a m1 caliber .30 springfield armory on back of rifle , the barrel is made by h&r in 7.62 nato sa 11010457 dated 5 65 was told it came the navy, the question is ,is it safe to put factory 7.62 x 51 win. without blowing up, I tried putting shell in front of barrel it looked a little tight not coming to the rifle case , could use your comments, thank you.

      1. @Don B, No one is going to answer your question because it could become a legal issue. Perhaps you could take it to a bona fide gunsmith for a physical in person inspection.

      2. @Don B, Try using the ammo that is stamped onto the barrel and refrain from ANY experimentation whatsoever.

        ALL attorneys for accident, injury, liability lawsuits will tell you the exact very same, AFTER THE FACT OF YOUR, “EXPERIMENTATION” else they would make no money off of your unlicensed, unauthorized, unregulated stupidity.


      3. Mr. Bozeman, I will not do like Mr. Romeu has done and comment on your question like you are foolish in asking it. Instead I will give you the same advice that Wild Bill did. And maybe a little more. First, the rifle you have is probably worth around $2000.00, so I would not experiment. Take it to a gunsmith and have him use a go/no-go guage or a field guage on it to determine headspace. Second, have him check the magazine (clip) area and make sure there is a spacer present. One is required for the M1 when converted to 7.62×51, since it is a shorter round. Without this spacer block, the rifle won’t feed. Third, if the headspace passes the go no-go guages or the field guage, I would use only match grade Hornady ammunition in the 165 grain to 168 grain weights, which are specifically designed for 7.62×51 rifles, but only after the REPUTABLE gunsmith has passed on the rifle as safe to fire. Also, just so we can clear up a few things, if you check with the Civilian Marksmanship Program, they will probably be able to tell you if you have a military conversion, and if you ship it to them, they will not only check it completely, but certify it as safe to fire with commercial and Nato ammunition when they are through. That may be your best bet. You can find them with any search engine. Hope this answers what I think is both a reasonable and legitimate question. Elton P. Green, SSG, USA, Inf. Ret.

        1. Some very good points, but to clarify, please, the spacer block in a Navy 7.62mm Mark 2 (M1) rifle is not required for feeding. It is optional, and only there to prevent someone from loading a clip of .30-06 into the rifle’s magazine. Many of the Navy’s rifles did not even have the spacer block.

          1. The spacer block for the 7.62×51 conversion was sometimes lost when the rifle was disassembled and not replaced. It was designed to allow the shorter cartridge to feed reliably, and was a necessary item for that in an M1. If your rifle feeds without it, that’s good. Most of them wouldn’t feed well without the block to help guide the round, due to the extra length of the receiver. It was also a problem with the prototype M14 due to the first receivers being converted from the longer M1 receiver. And on occasion when the first M1 conversions were fired and the clip ejected, sometimes the spacer would either eject or be partially ejected and block the action. If you have questions about reliable function and the spacer in the M1 Garand, email the CMP and they will tell you why they put them in their conversions.
            SSG Elton P. Green, USA, Inf., (Ret.)

            1. Mr.Green:
              Re Garands converted to 7.62MMNATO or .308 Win., yes there are differences between Military and Commercial rounds on the referenced calibers,as I recall from when I was active in competitive rifler shooting, I had seen a couple of Garands shooting .308Win.and or the NATO round. Re the “block”you mentioned, correct me if I’m wrong, but that would be part of the story, as a new barrel would be required.

            2. Alan, you are correct. The rifle is re-barrelled to 7.62 NATO, and a spacer block is installed. The spacer is there because the magazine (or clip) well is designed for the 30-06 and it acts as a filler and guide to ensure reliable feeding.

            3. You’re rifle is an M1 Grand conversation to 7.62 NATO. This was done to try to save some money and give the Navy a target rifle due to a shortage of available M14 rifles. This is why it’s marked 7.62 on the receiver. If the mag well block is missing a .30 cal clip can be loaded mistakenly. The 7.62 chamber is 1/2 inch shorter. If you run the bolt home the .30 cal round will go into the chamber and stop bolt won’t. This can cause an out of battery detonation destroying the rifle and possibly killing the shorter. If you’re rifle dosent have one you should replace it. Fulton Armory sells them

            4. The spacer block is only there to prevent a clip loaded with .30 caliber ammunition from being loaded into the receiver. When the bolt runs forward the .5″ round will stop and could cause an out of battery detonation with tragic results to the rifle, the shooter and the shooter next to him. I saw this actually happen once. Fortunately nobody got hurt but the rifle didn’t survive. If you spend enough time on shooting ranges you’ll see it all sooner or later

            5. Mr. Furbush is also correct, in that the block kept the Navy from using clips of 30-06 ammunition in a rifle chambered for 7.62 NATO. It also serves as a guide to keep the shorter round orientated properly for reliable feeding. Both the CMP and Fulton Armory will be glad to sell you one, and it isn’t hard to install.
              So far, we’ve discussed the difference between .308 Win. and 7.62 NATO, which is in areas such as brass thickness and primer crimps etc., but we haven’t differences in brands of brass, either .308 or 7.62. I think that should be mentioned too, as it will effect what commercial ammunition or brass one uses in either firing or reloading for the rifle. There are differences in thickness, uniformity, strength, ductile properties, annealing and brittleness between military brass manufactures’ products, as there are between the civilian producers. All military brass is not the same. All civilian brass is not the same. Some manufacturers just make better brass than others. Personally, I tend to stay away from Federal brass for reloading because I have found it to be a little soft in the area of the cartridge face. I’ve had Federal brass spread the primer pocket in my HK 91 on several occasions when Remington or Winchester functioned flawlessly and showed no sign of case head expansion. I can get 7 or 8 reloads out of Remington, Hornaday or Lake City (10 or 12 from LC) without the brass cracking in the neck due to work hardening. Winchester is generally good for maybe 5 reloads because it is thinner in the neck and becomes brittle more quickly. I haven’t reloaded much Nosler, Norma or Lapua brass because I’m not rich enough to afford a diet of the high priced spread. Also, Remington seems to be very uniform in neck thickness and neck runout. Lake City Match (when you can get it) is also extremely consistent in these areas. If you’re going to run a gas gun like the M1A, the stronger brass is a must. If your loads are going to be accurate, the consistency between pieces of brass is a good thing. If you want accuracy, the brass has to be consistent in runout, neck thickness and neck tension. If you don’t want head separation or primer pocket blowouts, it has to be hard enough not to expand under pressure at the head and web. If you want the brass to last through a few reloadings, the neck can’t be brittle or too thin or it will work harden early and crack. Personally, I’ve had really good experiences with Remington and Hornaday brass in all the calibers I shoot, but every rifle is different and some rifles just like certain brands of brass. But if you re-size and reload carefully, all of the good commercial .308 Win. manufacturers’ brass will function in the 7.62 Nato rifle (M1A, M1 Garand or FN, HK, AR10 type rifles) and give good to great accuracy. My HK will shoot into about 1.2″ at 100 yards with the typically poor trigger pull that that model rifle is known for (around 8 pounds). Also, if you want a really good bullet for the M1A for long distance, the 175 grain Sierra Matchking lists as a BC of .5 approximately, and will stay supersonic out to around 900 to 1000 yards at a M.V. of about 2550fps. That’s the standard mv for the Lake City Match load with this bullet. It was specifically designed by Sierra as a replacement for the 173 grain Match bullet used into the late 80’s by Lake City with the intent that it would be supersonic to at least 1000 yards. Its even better in a 30-06 or a .300 Winchester Magnum due to the considerable increase in initial velocity. I’m currently using the Sierra Prohunter 180 grain Spitzer for shooting out to about 600 yards here in Colorado, due to its low cost and extremely good accuracy. It gets about 2520fps from a 22 inch barrel loaded in LC brass with Remington 9 1/2 primers and appropriate powders. Very consistent and highly accurate. Due to the altitude here in Colorado, this bullet performs like a 180 grain matchking at sea level as far as trajectory is concerned. And I just like the down-range performance of heavier bullets.
              Elton P. Green SSG. USA. Inf., (Ret.)

    22. I have a pair of Indian made Enfield rifles in 7.62 NATO. I have had one round that the head separated from the case while I was shooting them at the range . The gas vented back into my face but fortunately I was wearing my razor fly shooting glasses. I was using Steel cased wolf 308. When this happened. I had already fired several hundred rounds out of the rifles with nonproblems. I no longer shoot anything but 762 Nato surplus through my various 762 bolt actions. I at one point purchase several cases of the steel case wolf 308 and have used it in most of my rifles without problem , but I’ve learned my lesson and will no longer do so .I have an Israeli k98 and 762 of VZ 58 in 7.62 a couple of FR-S and a couple of FR sevens. All of them have been put on a brass 7.62 NATO Surplus Ammo diet since the incident with my wolf Steelcase. I shot the rest of the Thousand round case of wolf through my M1As and my lrb M14SA without any problems

    23. Great article and a reminder for myself, since I own a M!A. After reading this article I went to my documentation and it listed my rifle as head spaced to 1.631. I believe this may be due to it being a fully loaded model, just a guess. I only shoot mil spec ammo in it, I had some commercial FMJ ammo where one case failed to eject and I had to remove it with a cleaning rod. I have not tried any major brands of hunting ammo, It may prove more reliable.

    24. Tom McHale, thanks for a well-done, genuinely helpful piece.

      I recently acquired a Mossberg 800AM in .308 Winchester, Mossberg’s entry into the center-fire weapon field. The weapon, because it was part of an estate ownership and though built in 1970 – 1972, is in 98% condition in both metal and woodwork.

      I called Mossberg to ask about the proper care and feeding of this beautiful lady. Their weapon specialist, while agreeing that the .308 is loaded more powerfully than the 7.62mm, strongly recommended that I not use the latter round in the weapon. He remarked that while I might get away with the practice of interchanging rounds, the 800AM was built and tested specifically for the civilian round. Out of courtesy he couched his observations about head-space and casing thickness in understandable terms, and I got the message.

      I have stayed alive with all my parts through some very dicey situations mostly because my Dad reared me to understand that when an expert tells me something, paying attention to it is about the smartest thing I can possibly do. And .308 in all its iterations is easy to acquire, anyhow.

      Thanks to you all for a fine discussion run.


      Harris Langford

    25. I have an M-1 Garand that was rechambered to 7.72 NATO and given the National Match treatment. It is hard on commercial .308 brass.

    26. Ha Ha , Because I’m a bit of a Dummy RE-Math and an OLD Marine at 81 yrs old and keeping up with the young studs! I’ll have to go with Viper in MT, and shoot what the gun calls for. Hold em and squeeze em gents! if your in the -V- ring I’d say your probably using the correct ammo.

      Semper Fi
      Machete Eddie
      Capt USMC (ret)

      1. Thanks for your service, and HuuuuuRahhhhhhh!

        It says what ammo to use right on the firearm. That’s what I run through each of mine except in the case of a firearm which has been certified for more than one (.357/.38Spl, .308/7.62, .22S/.22L/.22LR). For 21+ years. I was provided the correct ammo for my issue firearms and I never had a problem of confusing calibers.

        DaveW, MSgt, USAF (Ret.)
        Defensor Fortis

    27. HK G3 were 7.62 NATO. One of the improvements PTR did was chamber in .308. I have the PTR 91 and it digests everything just fine. .308 is more accurate though.

    28. I have a Mossberg .308 and out of curiosity I called the company and ask them. The gentleman I spoke with
      said I could shoot them with no problem. He said the biggest difference was the headspace and the brass.
      The military 7.62 was a little heaver but had not effect on the weapon. He did say that personally he
      would not soot the .308 in a weapon designed for military usage and the 7.62 though he had done so
      and had not had any problems but preferred to used modern weapons with the correct caliber as being
      the safest alternative. I have rant over 100 rounds of both types thru my weapon so far and have inspected
      the weapon with a bore scope and noticed no change or problem in the chamber nor the bolt facing.

    29. If their was a dangerous difference in the calibers then we would hear not stop stories of shooters blowing off their faces with the wrong round whether its 308 or a 223 issue. I can even recall about hearing such a story but only ones involving shotguns or five-seven reloads.

    30. I have two Savage Model 99’s. All I have shot in them is 308 commercial rounds. I have been considering trying some 7.62 X 51 FMJ to see how they perform, but now I may just stay with commercial ammo. I believe both were made in the 1950’s and are gaining value and I do not want to damage them in any way. Additionally, I have a Ruger Scout that says 308, but does not say 7.62 X 51. I guess I’ll contact the Ruger company to see if they have recommendations.

      1. I had the Ruger Gunsite Scout in .308 and I did contact Ruger about shooting 7.62 NATO through it and the reply that I got was that you can absolutely shoot 7.62 through it.

      2. I had a Savage 99 in .308 and no way the bolt would close on 7.62. I also have a Savage Hog Hunter in .308 and it seems to have a bit more generous chambering as I have been able to easily close the bolt on SOME military rounds. But the real question should be “Why in the world would you want to try this??”. A Savage 99 is never going to be used for long distance shots and should never be considered as a plinker that you are going to take to the range and blast away on cheap surplus rounds. So where is the need for the 7.62? Are you telling me that your ammo suppler doesn’t have .308? You may have fallen in love with the price break on European 7.62 surplus, but please consider getting something that that round was intended for, like a full auto M60.

      3. fishunter.
        i own 4 savage model 99’s.
        one in 250 savage, two in 300 savage, and the last one in caliber 308 winchester.
        in that one i’d NEVER SHOOT 7.62×51 IN IT.
        my advice to all here is STICK to the caliber your firearm was designed to shoot.

    31. Some days I’m just not smart enough to shoot a gun. That will be the day I have a 7.62 or 308. Whew. Seems to me the only safe thing is to fire what the barrel stamp indicates.

      1. Ahhh! Trying to impose common sense and logic into the world of firearms? Are you sure that’s a safe thing to do on an online forum full of people that refuse to use common sense and logic?

    32. I use 7.62X51 brass for my handloads that I run in a gas gun that I built.
      I trim to length( .308) and load using the .308 data. I look for pressure as I develop loads .

    33. I have a Browning Hog Stalker semi auto marked 308 only. It appears in all aspects to be the same rifle as the FNAR with exception to the camo finish on my rifle. I see the FNAR is stamped 7.62X51. Can you explain the difference?

      1. Yes, in one rifle the manufacture is telling you to use, .308 ammo and the other manufacturer is telling you to use 7.62×51 ammo???

      2. In reviewing a lot of the responses to this particular article it is showing proof to the world that the Liberals are right that there should be a disarmament being that a lot of you do not deserve or need to have firearms in your possession just by the dumbasses questions I am seeing.

        I have a website SELLING “Common Sense”! Feel free to stop by and purchase all you want at any time!

      3. The reason that the rifles are similar is that Fabrique Nationale and Browning have been affiliated for about 90 years. They are the same rifle made by probably the same factory with different names because one is sold in the US and one is sold in Europe. In the case of the FN rifle, it is stamped with the metric designation for the .308 Winchester. When I was stationed in Europe (notably Germany) I talked with several German gunsmiths. The commercial version of the 7.62 Nato is labeled 7.62X51, and exactly corresponds to the .308 Winchester. Also, further evidence that the 7.62 Nato and the .308 Winchester have the same external dimensions is that the M24 and M40/a1/a2 sniping rifles are stamped 7.62 Nato and the snipers that fire them are issued mostly Federal Gold Medal Match ammunition for use in them. These rifles have a 7.62×51 that is reamed to match specifications and headspace tolerances, and won’t chamber some of the foreign ammunition that is not held to the tolerances required by the US military. However, they will chamber American, German, English and Belgian 7.62X51 just fine because this ammunition is held to close tolerances. In fact, if you read FM 23-10, Sniper Training, when the M118, M118 LR ammo or equivalent isnt available, regular ball is used, after testing lot numbers for accuracy. This was true for the M21 system (highly accurized M14 with match chamber and barrel) too. Also, both Lake City National Match 7.62 and Federal Gold Medal match Grade .308 have been used interchangeably along with Hornaday match ammunition in .308 at the Camp Perry National Matches for around 40 years. Properly manufactured 7.62X51 NATO ammunition can be used safely in rifles made for .308 Win., and .308 can be used in any rifle chambered for 7.62 X 51 NATO as long as the chamber passes a head-space test with either the go, no-go guages or a field guage. Just remember that some of the rifles and ammunition made in 2nd or 3rd tier countries have poor quality control and don’t necessarily meet NATO specification regarding cartridge or chamber dimensions or head-space tolerances. If I were going to buy surplus ammunition is this caliber, I would stick with that manufactured in Israel, Brittain, Germany or Belgium. They have good quality control. Keep in mind also that any US commercial rifle is proof tested. It is checked for pressures of around 75,000 psi to insure its safety. Good hunting.
        Elton P. Green, SSG, USA, INF. Ret.

    34. I don’t think the pressure in the Tsar Bomba was enough to “alter the trajectory of Michael Moore’s daily Krispy Kreme run.”

    35. Have a browning short trac marked 308 only. Have fired IMI 7.62 and functioned OK. Should I continue to use it or go 308 only.

      1. The IMI commercial 7.62X51 is .308 Winchester made by Israel using the metric designation. (Germany does the same thing with its commercial .308 because they also use the metric system, although when I was stationed in Germany, some of their .308 Winchester was stamped with both designations.) It is made to US tolerances, and I have fired it in both bolt guns and semi-autos extensively as practice ammunition. It is also very good brass for reloading. Don’t be afraid of it. I use it in my Remington 700, a Savage model 10, and an H&K 91. It functions beautifully and is quite accurate. Your Browning (good rifle, by the way) should be able to digest it pretty much without a hitch until you shoot the barrel out. It also works very well in M1A rifles as long as the rifle is in good condition.
        Elton Green SSG, USA, INF, (Ret.)

      2. The country of Israel uses the metric system. The IMI brand of ammunition is labeled accordingly. IMI 7.62X51 commercial ammunition is .308 Winchester ammunition labeled under the metric designation. Germany does the same thing with their .308 Winchester commercial ammunition too. But since they accommodate American shooters and hunters (mostly military stationed there) they will label most of their ammunition as .308 win/7.62X51. (I know that Germany does this because I was stationed in Germany for about 4 years.) The IMI brand of ammunition is completely safe in your rifle as long as your rifle is in good condition. It is made to SAAMI specs by one of the countries with the best quality control in the world. I’ve used IMI ammunition as practice ammo in Remington 700’s, a Savage model 10, several of my friend’s M1A’s and my HK 91 with no problems of any kind, and the brass is great for reloading. By the way, that’s a really nice rifle.
        Elton P. Green SSG, USA, INF. (Ret.)

    36. Have a Browning Short Trac says 308 only. Have fired IMI 7.62 and functioned fine. Should I continue or 308 only?

    37. I’ve shot both in my Marlin .308, never had a problem with length of 7.62. Nwow that’s not to say I won’t but I’ve fired 1000’s of rounds with not problems.

    38. I just read your your article about MOA vs MIL. My question is how does a 20 MOA rail figure in to tje calculation?

      1. A 20 MOA rail doesn’t affect calculations at all. It simply gives you more range adjustment. If you’re not zeroed at 100, and adjusting your elevation for longer shots, you don’t need a 20 MOA rail.

      2. Forget the 20 MOA rail. Get a Shepherd P2 or one of their 4X14 scopes with the dual reticle bullet drop and range finding reticle built in for 1,000 yards or in the new scopes, 1,200 yards on the vertical cross hair. I have five of these scopes mounted on two 30-06’s, two 300 Winchester Magnums and one 35 Whelen. Shepherd has reticles that are matched to all these calibers and several more. The P2 is designed especially for the .308 Winchester/7.62X51 NATO cartridge using 165gr through 175 grain match bullets, and will be within one minute of angle of drop out to 1,000 yards on an M1A. They’re currently being made by Salvo and you can find them by googling Sheph Scopes LTD. or Salvo Inc. They’re listed as the DRS scope system. I have gotten first round hits with a Shepherd in all of my rifles out to 800 yards, and have shot to 1,000 yards on a few occasions with them and when I had windage right, gotten either first or second round hits. These scopes are very reasonable and range from around $800.00 for their 3X10 power up to $1,500 for their 6X24 which compensates out to 1,200 plus yards on the vertical reticule. Proper windage can be dialed in on the Shepherd and observed in the reticle, due to the ranging reticle being in the front focal plane and the cross hair in the rear focal plane. You can dial in exact windage and measure your windage against the horizontal tic marks, which are 1 inch at 100 yards. Then you just rezero for no wind by dialing back to “0” on the horizontal scale in the reticle. No system is ever perfect, but this system and a little research into altitude effects with your ammunition will let you hit at distance easier than anything else I have ever used. I do know it makes 600 yard shots at steel seem easy. I don’t get to shoot much farther than that now, because there just aren’t many ranges here that go past 600 yards, and to shoot farther than that I need a spotter to call wind and hits. Check out the Shepherd. It works.
        Elton P. Green SSG USA, Inf. (Ret.)

    39. Please note: the difference in headspace length is only 5 and 1/2 thousandths (or 55 ten thousandths) of an inch according to the numbers you show. The only way you can get 15 thousandths difference is between .308 min and 7.62 max.

      1. It’s no different than a barrel stamp 5.56 or .223. It means for the manufacturer’s warranty purposes they will accept and you will be in compliance within their limits of any liability to use either or round in that rifle.

        1. That is not correct. 5.56 military rounds can be much longer than .223 by design not just by stacking tolerances. If such a military load is chambered in a .223 the projectile will be lodged against the rifling creating a potentially catastrophic high pressure condition.

          When we use civilian .308 round in a military chamber we are fighting the larger chamber allowances in the 7.62 rifled. The thin civilian brass in conjunction with large military chamber allowances can create a situation where we see ruptured cases. Except for the poor quality control demonstrated in some military surplus ammo that was mentioned in the article, that is the only real concern.

          1. Well golly gee? Then I guess you better hurry up and run and tell the manufacturers of these chambered rifles that you know so much more better than them or their engineers???

            1. you guys are all nucking futts!…..just shoot what you’re supposed to shoot through the gun…….geeeeez….

        2. Now there is an answer that explains my whole Question Thank you very much. I am happy to find out that I am not a blind monkey on crack. Some people are not worth the effort to talk tp pr about

      2. Mr. Romeu is correct. If it is stamped both 7.62X51 and .308 Win. it is safe to shoot both. Just make sure the 7.62X51 NATO is within tolerances and you’ll be ok. If it chambers with little or no effort it is within tolerances. And yes, some 5.56X45 NATO is longer than .223 Remington ammunition, but that is overall length, not differences in casing. If the rifle is stamped to accept both .223 Rem and 5.56 NATO, it has a chamber with a long (military specs) leade in front of the casing, and is safe with the 62 grain bullet loaded in surplus ammunition. If you’re going to use heavier bullets, keep them at that overall cartridge length and you will be sufficiently within chamber length tolerances to be safe. By the way, I don’t think you can find milsurp ammo for 5.56 with bullets that weigh more than about 62 grains anyway. But again, I’d stay away from the Russian steel cased and some of the stuff from third world countries because of poor to no quality control unless you’re buying it just for the components.
        Elton P. Green SSG USA, INF. (Ret.)

      1. Probably just fine as long as it’s from a modern and reputable manufacturer. If it’s from Breszchzzk Ordnance arsenal made in 1958 then that might be a different story 🙂

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