New Military Caliber as 5.56×45 Sunsets


New Military Caliber as 5.56x45 Sunsets
New Military Caliber as 5.56×45 Sunsets

Ft Collins, CO –-( Caliber Controversy!

After decades of piously assuring us the 5.56×45 round was “adequate” for military purposes, despite mounting complaints (unsatisfactory range and penetration), dating back to Vietnam, the Pentagon has apparently finally changed its mind.

In spite of a dreary series of failed “wonder bullets” that have, every few years, come forth to “upgrade” the 5.56 round, faith that the 5.56 can ever be “adequate” is fading!

Just as the Marines are buying the HK 416 (M27), a gas-piston AR (in 5.56×45 caliber), to replace aging M4s, Congress and the Army are putting the breaks on that project.

After fifty years of pointless hope that the 5.56×45 round might really be “adequate,” a new, bigger military caliber may now be about to make its debut!

When the AR (in 5.56×45 caliber) first reared its head, and garnered the attention of then Secretary of Defense McNamara, it was slated to gradually replace only the M1 Carbine, never the M1 Garand, later the short-lived M14.

The M1 Carbine, manufactured by the millions during WWII, was originally intended only for rear-area defense and police actions. It was never intended to be a front-line, battle rifle, although it eventually found its way into every corner of the campaign during WWII and Korea.

When I was in Vietnam in 1968, M1 Carbines were still around in large numbers. I saw (and used) plenty of them.

Yet, the AR (in 5.56×45 caliber) somehow eventually became the main, battle rifle of all US Forces, and remains in that status to this day. This, despite continuous misgivings about its adequacy that have been desperately voiced since Vietnam.

Up until now, the Pentagon as assured us that these qualms about adequacy were all in our imaginations!

That is apparently about to change.

Of course, the Pentagon will never admit they’ve been wrong all this time. They’ll simply say “It’s time to move on.”

It was “time to move on” fifty years ago!

Stay tuned!


Defense Training International, Inc

About John Farnam & Defense Training International, Inc
As a defensive weapons and tactics instructor John Farnam will urge you, based on your own beliefs, to make up your mind in advance as to what you would do when faced with an imminent lethal threat. You should, of course, also decide what preparations you should make in advance if any. Defense Training International wants to make sure that their students fully understand the physical, legal, psychological, and societal consequences of their actions or in-actions.

It is our duty to make you aware of certain unpleasant physical realities intrinsic to the Planet Earth. Mr. Farnam is happy to be your counselor and advisor. Visit:

  • 250 thoughts on “New Military Caliber as 5.56×45 Sunsets

    1. all of a sudden got to have english lit degree to squeeze the trigger … and LOOK good doing it.

      maybe that looking better part is why they opt’d to allow efeminates on the battlefront

      1. @byproduct, That’s a PsyOps issue… Do you actually think that the enemy would want to shoot at a bunch of college aged American hotties?

        Speaking of which, why isn’t there already a Military Hotties reality TV show?

      1. Ok gregory, and exactly where did I say anything about the “Air Force” not being involved in the adoption of the M16? From the replies you get it’s pretty obvious that no one agrees with your blabbering. \In this case there is an entire article devoted to the specifics of how the M16 was adopted by the Air Force and THEN Secretary McNamara who was also a fan of the AR-15 stopped all new procurements of the M14 rifle and the following year, ordered the Corps to work with every branch of the military to adopt the AR-15 rifle as the standard service rifle of the entire U.S. military. The M16 was born. Interesting how Special Forces isn’t mention at all; not even the single sentence that said so in all of you other “references”! What is true is that, after Vietnam, Special Forces was instrumental in establishing new modifications to the M16 which eventually led to the M4 and the host of aftermarket add-ons. It is also SF that has led to the creation of most of the new AR calibers that have become popular and mentioned in this comment section.

          Picture of JFK in the White House inspecting an M16 with a General Clinton holding a crossbow.
          General Curtis LeMay saw the M16 and want it for SAC for USAF to guard the B52s.
          McNamara was behind the “new” gun and rushed it through military acceptance. In tests with commercial ammunition loaded with IMR stick powders the gun ran w/o getting so dirty cleaning was not an issue. But shortages of IMR powder resulted in a change to easier and faster to manufacture ball powder.
          Ball powder left more carbon residue and combined with the high humidity in Vietnam jungles combined with a non-chrome lined barrel and chamber resulted in many stoppages.
          After 50 years the issues of everything except low power and range have been solved.
          The idea was to have a weapons system lighter in weight than the M14 so than more ammunition could be carried into combat.
          The 7.62×51 NATO is effective but heavier. If an aluminum case or even a caseless ammunition in 30 caliber would give a wider range of projectile types, longer effective range.
          The combat weight has to be carried on foot, by helicopters. Even trucks have payload limits.
          Ask a Marine, a SEAL or combat survivor what they need and then do it. The cost of 250,000 new rifles pales when compared to billions of rounds of ammunition. The best ammo saves the lives of our guys.

    2. Somebody been watching way too many Tom Berenger: Sniper movies. Snipers do not win battles or wars. Overwhelming force, the best tactics and strategy and the most advanced tech & equipment does however when properly applied.

      1. @Nottinghill

        You know, For someone who referenced fiction as a reason to claim validity for his own argument, you might want to look up actual history and facts before making blanket statements.

        You see had it not been for snipers, or had British snipers been more effective we might have lost the revolutionary war. Washington’s reluctance to settle for anything less than European style line infantry was a large factory in our early struggles during the Revolutionary war. The backwoodsmen coming out of Tennessee and western Pennsylvania with their squirrel and deer rifles, along with Washington’s reluctant admittance to a company of elite riflemen to be formed from the best shots that could be found in service at the time turned several battles and were instrumental in the victories that turned the tide of the revolutionary war, particularly Saratoga. Timothy Murphy, one of the elite shots of Morgan’s Riflemen, was responsible for the sniping of two high level targets during the battle that directly influenced the outcome. Most notable of these was General Simon Fraser, who Murphy shot at a distance of over 300 yards from a perch in a tree with a double barrel rifle(Speculated, but likely historically in regards to the rifle itself).

        Other cases of British soldiers writing letters detailing witnessing feats of American Marksmanship at rifle shoots while in custody as POWs have been recorded, including the lament of one to the tune of “My word, if they all can shoot like this we have no hope of putting down this rebellion. These men take shots and hit their mark past 300 and 400 yards as a game!”

        It was snipers in World War two that ultimately stopped Germany on the eastern Front and turned the tide to allow Russia to recover. 11,000 Finns acting as riflemen, picking targets and using sniper methodology resisted and decimated over 45,000 Russian soldiers during the Winter war. It was only when they ran out of ammunition did they finally succumb to the superior numbers of Russian conscripts. The Sniper methodology used by P-38 Pilots in the pacific to ambush and shoot down Yamamoto’s personal transport aircraft far behind enemy lines with pinpoint precision.

        Carlos Hathcock II, pioneered modern sniper doctrine during the Vietnam war which was instrumental in supporting our troops and limiting the damage done to our own troops. A single man, with relatively few kills compared to the most advanced tech of the day, but who was yet so famous and despised by the enemy that his trademark become the name they knew him by, placing years worth of wages as a bounty on his head in country.

        Jack Coughlin, a Marine Sniper who pioneered new methods in rapid transport and sniper tactics during Operation Iraqi Freedom, or Kris Kyle…..

        I could go on and on, story after story straight from the pages of history books. You really should have done some research first. “The Best Tactics”? The ability of the sniper to surgically remove a strategic target, interrupt communications pathways, advance scouting and intelligence gathering, as well as instill fear in forces hundreds of times the size of himself.. What on earth makes you think that is not one of the biggest tactical assets we have? If there are some people who watch way too many movies, perhaps on the reverse you have not watched enough. You may want to consider doing an in depth Character study of Major Powers from “Heartbreak Ridge” as you seem to have played him to a tee. Seriously, so many words…….

        1. Here’s what I have gleaned from the web

          .264 USA appears to be designed from the outset for composite metallic polymer cartridge case configuration.
          264 USA may be a shortened 35 remington case.?
          The 264 USA has 46 grains H2O case capacity. Similar to 280 Brit.?
          With a composite plastic and brass case (telescoped?), the 107 grain 264 USA (CTA = composite telescoped ammo?), is nearly as light as the brass case 5.56, 13.6 grams to 12 grams respectively. The 556 being lighter.
          264 USA (6.5×48) = 10.5 to 11.5 lb/ft
          6.5 grendel = 8.5
          5.56×45 = 4.1
          6.8 SPC (6.8×43) = 8.2
          9×18 luger = 2.2

          264 USA has higher performance than 5.56 ( maybe .308). It has increased recoil, increased weight, increased heat flux (barrel heating up) which could reduce rate of fire and reduce accuracy.

          264 USA
          Projectile .264
          Neck .292
          Shoulder .4335 base too?
          Rim .4449
          Case length 1.873 inches , 48mm?
          Overall length 2.6 + inches

    3. The ‘AR’ platform rifles will not be dismissed immediately. They will be phased out. America’s new rifle WILL BE a cartridge-less weight reduced multi-barreled rifle platform that will maximize projectiles carried and fired per trigger pull while incorporating state-of-the-art accessories. The caliber will be between 6.5 and 6.8, favoring the 6.5. Bullet weights will be between 90 – 140. Most likely they will settle on a 115 – 130grn projectile speed of 3100 – 3400 fps for both long range, amour piercing and specialty H/E applications (including in/on projectile guidance systems). Rifles and pistols will use the same calibers.
      Servicemen will be able to carry 750 – 1000 projectiles per person. If jacketed robotics are used (DARPA) this will mean multiple back-up power supplies and atleast a threefold increase in projectiles carried per soldier.
      The ‘age of gunpowder’ is over in America’s future warfare.

      1. Don’t you know that weapons that use electromagnetic forces to accelerate a projectile take massive amounts of electrical power & are very inefficient. Why do you think that the Zumwalt class of destroyers have more that twice the electric power generation than required to propel the vessel at flank speed. Check out the Navy’s rail gun prototype. Only nuclear reactions release more energy per unit mass than chemical reactions.

      2. Found this looking up Eugene Stoner,

        We left with 72 men in our platoon and came back with 19, Believe it or not, you know what killed most of us? Our own rifle. Practically every one of our dead was found with his (M16) torn down next to him where he had been trying to fix it.

        — Marine Corps Rifleman, Vietnam.[65][66]

        1. Yep! Ball powder and dirt jambing the bolt carrier groups and no forward assist to aid in forcing the by carrier groups home so they could clear whatever jambs they had to get back into the fight.

          Now we have cleaner burning propellants and a forward assist along with all the other multitudes of accessories and items that we can utilize to improve the M16 M4 AR-15 platform as well as LSA and the proper cleaning gear.

          1. Cleaner burning propellants, and, some really hot propellants. Hodgdon super performance is one I have tried. It is little balls, meters well, and I have flattened some primers I unintentionally in a 30.06 . Scary hot powder, but, higher pressures by far. The military may have some blended powders or solid propellants that are duplex? Superperformance powder is for larger cases and lighter projectiles going 200 + fps faster than before. The battle field calls for a different setup? Smaller volume and lighter weight ammo sending heavier bullets faster…tough combo. That and a perfected AR style platform could be the target next generation battle field rifle.

        2. The Vietnam War M16 and the ammunition was an experiment. They did not even issue a cleaning kit or a maintenance manual. The change from IMR to WW ball powder, the raw steel chambers and a host of other problems made the M16 a bad rifle.
          The last half century has has the M4 a different beast. Is it perfect? Hell no! WWIII was supposed to be fought with airplanes, missiles and tactical nukes. The battlefield was supposed to be city clearing and jungles. But we’re in mountain to mountain 600-1,000 yard battles Our enemies now wear body armor.
          Our troops travel by weight limited helicopters.
          The AR platform has been proven. The 7.62×51/M2 Ball has nearly 100 years of testing and battlefield experience. The cost of buying 1 million completely new rifles, uppers and lowers is a drop in the bucket.
          The size limitations of the M16/M4 lower limits the long range of potential against light vehicles and body armor.
          The 6.80 SPC is an attempt to make do with the replaceable lower. The 300 BLK is a handgun cartridge optimized for close range quiet power and it isn’t suitable for general issue any more than a 338 Lapua would.
          An AR pattern M14 with an 18 inch barrel and a 30 round magazine with all the versatility or the M4 is probably the best idea. Development of of lighter weight cases, a 1-9″ twist and projectiles from 120- to 250 grain sub sonic will make an arm that can take out a sentry or a vehicle at half a mile.

            1. The M14 was the product of NATO standardizing on one cartridge and the Ordinance Corps being hidebound & sabotaging rifle trials. The Army didn’t want an intermediate cartridge like the British 284. The 7.62X51 is shorter than the 30-06 however it has essentially the same ballistics by using higher chamber pressure. Then for the stated reason they could use the same arsenal tooling as the M1 Garand they developed the M14 which is basically an M1 with detachable box magazine & select fire. In auto mode the M14 is totally uncontrolable; since the barrel is not direct inline with the stock & the recoil of the 308. The Army wasn’t gong to ever adopt the superior FAL. The FAL became the battle rifle of the free world & the M14is the battle rifle with the shortest service life. The pig headedness of the perfume princes at the Pentagon had solders & marines going into battle in the jungles of Vietnam with obsolete inferior weapons. The M2 carbine was a better choice for combat in Vietnam. In 1969 in BCT I qualified qualified on the M14 & M16. With the M14 the instructions were to not use auto fire with the M14 in fact the oes we used had the auto mode disabled. Not being a grunt I didn’t fire the M16 much. Once I shot up an ammo can through my M16 in auto at the rats in the Cu Chi dump. It is a real blast when uncle sugar is buying the ammo.
              P.S. The roller delayed blowback operating system of the CETME/H&K G3 pattern rifles are the most impervious to environmental conditions of any rifle design. Their drawback is weight.

            2. @ JD

              Try this. The weight of a M14 is around 9 pounds 4 ounces. The FAL comes in at 9 pounds 8 ounces. This is unloaded weight. Fully loaded both are right around 11 pounds. The FAL was never designed for the 7.62×51 cartridge, but was adapted due to the aforementioned nato requirements much like the original development of the Garand rifle. Two rifles, similar weight, same cartridge, and…. Wait for it. SAME ISSUES!

              Both rifles had the same problems with fully automatic fire when they originally came out, both used the same cartridge, and both were roughly the same in weight and handling characteristics. Both were notoriously difficult to control due to being far too light weight for the cartridge (Think BAR in terms of Direct comparison), and both had the same fix applied as there were also versions of the FAL made in semi automatic only specifically because of this. Both were BATTLE RIFLES. Before you have tried to characterize the M14 as an assault rifle, and that is not true. The major reason why the US never adopted the FAL was because it was not an American weapon platform. The FAL was adopted in Europe through NATO because of Fabrique Nationale, which was Europe’s version of Springfield Armory. The FAL is not Superior. The rifles themselves are actually on pretty equal footing. The one area in which the FAL may be considered superior has nothing to do with combat performance, but rather supply. Its a much easier rifle to manufacture. Plain and simple.

              Now, we get it. You have a personal bug up your butt about the M14. You don’t like it, and you know what? You are more than welcome to have that opinion. Quite frankly however, watching you try to substitute your opinion for fact in opposition to reality is really beginning to get old. Having said that, here is my opinion. Seeing you try to repeatedly beat this dead horse is the exact same thing as two old hunters arguing over the superiority of the 30-30 and 32 Special.

              Shoot what you like and leave it at that. We will do the same.

    4. Whatever new cartridge the service comes with will hopefully be at least 6mm to 7mm. I would think 260 Remington makes sense related to the parent .308 case. It seems like the m14 platform would work just fine. I can see the service keeping the 5.56 and the m4 platform for what it does best. I have noticed that powders have improved significantly in the last decade. Projectiles have gotten better also. It is imperative that our warriors get the best equipment we can provide. And, we as a nation have to be ready to change, adapt and prepare ourselves for the new challenges the world offers.

      1. The M14 platform is a POS as an assault rifle. I shot it once in auto mode in BCT in 1969. Even the range officer couldn’t control it in auto mode. I believe it is where the term pray & spray came from. If the cartridge selected won’t fit in an M16 form factor rifle an AR10, FN/FAL or HK rifle or something new would have to be used. The SCAR Heavy is too heavy for the grunt. The advantage of the AR10 platform is the manual of arms is the same as M4/M16.

            1. @Ammoland

              The only thing I question with concern about such a system is whether or not it will allow those who routinely commit to falsehoods to go back and alter or altogether delete comments as a means of covering it up.

              We currently have accountability, as each man’s words remain unedited for all to see, with date and time stamped prominently on the forefront. When outright lies or hypocrisy are displayed and pointed out, will they now be able to go back, edit, or delete the evidence so they may then feign ignorance or denounce those that called them out for accountability?

              Hope to hear some clarification on this, as ammoland has been one of the most honest and accountable sites pertaining to editorial comment in this day and age. It would be a shame to see it follow the often referenced “Deleted Tweet” where screen captures are necessary to ensure integrity between individuals. Further information would be graciously appreciated.

          1. @ Greg

            Surprised no one bothered to point out the basic difference between “Assault Rifle” and “Battle Rifle”, much less the sheer duplicity of citing The FN/FAL platform as it was never designed to handle the 7.62 and thus had the exact same issue with recoil as was cited being the downfall of the M14. So many words.

        1. Old Marine >>> DJ
          Funny that you call the m14 A “POS” when most snipers used it for their backup and night time rifle.
          I think their experience and choice makes your statement immaterial. True they didn’t use the full auto position but other than that still a great weapon that is known today as th M!A!… A dam good rifle.This is basically the third version of the M1 Garand that proved good in three wars and still one of the most dependable rifles ever made. With Iron sights its’s good even to 600-800 yards and with a scope I would not want to be within 1500 yards of an enemy shooting one. No matter what rifle /cal. you can defend yourself with. the M1A1 is a fatal weapon to go up against, that’s why snipers liked to use it.

          1. I believe you misread what was said, although I totally agree that calling the M14 a “POS” for any reason is ignorant. JD was referring to it as an “assault” rifle, when it was actually designed and called a “Battle” rifle.
            The M14 is one of the best rifles ever produced and is the weapon I learned with in Special Forces Sniper School in the early 80’s – it was called the XM21 (M14, floated, with ART1/2 scope. Later we switched to the M24 (Remington 700 bolt action). Biggest problem with the M14 being an “assault” weapon is the weight.

            1. The 7.62X51 is not an intermediate cartridge which is an essential part of the description of an assault rifle. The StG44, the prototypical assault rifle, was chambered in the 8mm Kurz.
              The US hasn’t fought in a conflict like WWII since WWII; so, a Battle Rifle hasn’t been appropriate & what possible conflict in the future is there where the squad members will need them? If the Wehrmacht had been equipped with StG44’s VE Day would have occurred at a latter date.
              The Germans lost in Russia for the same reason as Napolean did, weather & overextended resupply lines.

      2. Tonight I get down on my knees and pray that the Pentagon chooses a new military battle cartridge that is the 6.5×47 Lapua, or something as powerful, or more powerful.
        140 grain 6.5 mm high BC projectile going 2600 to 2700 fps. ~50,000 CUP pressure.

        1. It pretty much runs neck-to-neck with the 308 which is already in service. The cost effectivity and availability of brass tosses the 6.5×47 out the window.

          1. 260 remington?
            6.5 grendel?
            243 Winchester?
            6mm Lee Navy?
            6.5 carcano aka 6.5 creedmore?
            6.5mm in the 223/5.56 case?
            .337 LEEroy?
            130 to 160 grain projectile going plenty fast…

        2. About 4 yearss ago, the Army sent out an RFP for ammo in .264 USA that had to meet the following specs:

          “2,875 ft/s with a 107gr lead-cored Sierra HPBT from a 16.7″ barrel, or 2,657 ft/s with a 123gr Sierra from the same length”

          As much as everyone would like to be able to carry around a fully automatic 30-mm cannon, there are limits on how much recoil the typical soldier can be trained to handle, and to how much ammo by weight he can hump. The Army Marksmanship Unit put a lot of study into just what improvements over 5.56 NATO were useful, and what was practical in a general infantry weapon before issuing the above spec. Ammo that meets that spec has better muzzle performance than 5.56 NATO (which is adequate) and BETTER downrange performance than 7.62 NATO. It’s pretty much state of the art when implemented with brass cartridges, but word is that the Army is looking hard at brass-pollymer cases (much like shotgun shells) to lighten the soldier’s load even more.

          1. The Army has been sucking BILLIONS of taxpayer money over these bloated, innefective boondoggles! It’s time to lett the Marine Grunts make these we decisions! We can no longer afford the Army’s ignorance in small arms.

            1. Ah, you mean the same crew (Marines) that gave us that musket called the M16A4? Ha. That’s funny right there.

            2. @El Mac-aroni, if it wasn’t for the Army Special Forces and cohesion with the u.s. Air Force and the Ordnance Corps monkeying everything up by accepting and using ball powder in the original M16, the Marines would have never seen them. You should pull your head out of your ass from time to time you would be able to breathe better and actually do your research.

            3. Gregory, you’re an idiot. Ball powder was being used in military small arms as early as WWII (civilian small arms in the 60s). Special Forces had nothing to do with the Army adopting anything prior to the ’80s; SF always got the short end of the stick when it came to supplies and equipment, that’s why we were always known as the guys who could do the most with the least! Why don’t you provide us with a link to the information to prove your claim.

            4. @RattlerJake

              By the way did your strange Uncle Bob give you that nickname “RattlerJake”

              here’s just one more out of the thousands of links available proclaiming the same information I already posted.

              You should check with your Uncle Bobby and let him know when the butt hurt stops?


            5. By the way gregory, it’s Einstein!

              Every article you provided makes the same generalized statement and NONE of them provide a source for their claim. But you believe what you want to, it’s obvious by your constant ad hominem attacks on most of the people on this site. You sound like a leftist troll! You’ve been called out on most of the crap you replied with! Compared to you I am an Einstein!

          2. a very few army & marine & other nco’s could work this out if there was no interference from countless, useless d-suckers who have to their “stamp” of approval on everything

        3. @Lee G, I really love my 6.5 Lapua, but I don’t necessarily think that it will be considered for a US Army round, the Fins can’t afford the bribe.
          @GR, Cost effectiveness would not eliminate the 6.5 Lapua cartridge from potentential US Military use.

    5. Just read an article on Wilson Combats new .300 HAMR cartridge. MAY just be the ticket for a new military cartridge. Uses reworked .5.56 brass, same BCG, same mags, etc…. Just a barrel change required.

        1. As an aside, Charles Lindbergh was on an island in the Pacific during WW2, the enemy was staying just outside of the kill zone of the aircraft we were flying due to refueling needs, running out of gas. A mechanic noticed Lindbergh’s always came back with extra fuel in it.
          As it turns out Lindbergh knew how to increase manifold pressure to get longer fly time and greater distance. He taught the pilots how to safely do it on their craft and for a while we caught the enemy by surprise and bombed the fuck out of them.
          As I understand it the enemy has longer ranging battle rifles and the 5.56 can’t keep up with the distance needed. So, serve up some better battle rifles and cartridges for long range contact with the enemy.

          1. Lindberg was an officer in the Army Air Corps prior to WWII. His activities against going to war again in Europe resulted in his resigning his commission.. When then war started FDR refused to let him join up again. Henry Ford hired him as a civilian test pilot.
            Lindbergh kept a War Diary which covers his combat “test flights.” These were illegal since he was a civilian.
            He also would have been an ACE if he still held his rank.
            Aircraft engines RPM is controlled by the propeller. A quick and dirty rule of thumb was to not exceed manifold pressure/rpm but this wastes fuel. Lindbergh taught to to run low rpm and high manifold pressure in cruise flight, leaning the engine. fuel mixture. Most WWII pilots were fresh out of flight school and were thrilleed to have the man who soloed the Atlantic teach them.

    6. You bitch and moan about the guy making 1 literary mistake and here I’m residing in a remote location having to use speech to text technology on a cellphone to communicate and and regardless how it looks on this end, by the time I hit the send button there is absolutely NO guarantee how it will come out on the other end or whether it will please everybody? For people so sensitive to perfection, in the words of Kurt Vonnegut, “Go f’ck yourself!”

    7. I do not know if anyone has commented from this perspective yet. If so then disregard but there were some reasons for the 5.56/7.62 adoption of the time.
      1. Testing of the day: given the adoption process of the day, there may/may not have been adequate ballistics testing. Also, politics might have gotten in the way. Without getting into the weeds on the “Why” ill continue with a more current issue.
      2. Lessons learned: Whichever caliber was adopted, the U.S. military has a rule that it uses to guide the thought process on all other small arms testing. Its a rule influenced, ironically, by the defeat of Japan during WW2. After WW2 ended, many studies were conducted. One of these studies asked a fairly straightforward question of “Why did Japan lose?”. The relevant part for purposes of this thread is mainly that Japan had a production problem. During the war, Japanese small arms manufacturers were prolific. The end result being that many different kinds of firearms were produced and each had a unique caliber. The end result on the fighting end was a mass of confusion for the logistical end of the spear: troops fighting would receive ammo that was not correct for the weapons they had. So what does this have to do with the U.S. military adopting a better caliber today? Simply put: training and supply.

      I spoke to a LtGen Lamoyne while i was an undergrad in college and he told me that replacing any caliber was problematic due to having to replace all equipment, update the supply chains, produce manuals for armorers, train armorers, etc. Initially, the cost of such an endeavor was daunting. So, to answer the question in a more direct way: yes. There are more accurate/better calibers than 5.55/7.62 but the military balances pricing over innovation because it has other ancillary factors to consider. Quite simply, the military doesnt have the infrastructure to produce those calibers in large enough quantities.

    8. 1. I expect that DoD will, once again, change nothing about the 5.56mm ammo we currently use – except perhaps to go back from the copper M855A1 round to the (now) venerable M855, because it’s cheaper and more accurate.
      2. That having been said, perhaps into the mix of suggested different calibers (I do like the Grendel for a 5.56mm replacement) we can add a change in bullets. Try a heavier match-grade bullet in 5.56mm: No need to change the firearms (though it WOULD perform better out of a 16 inch as opposed to a 14.5 inch barrel), and would be more useful at all ranges out to 500-600 meters than the 62 grain bullets, while still usable at CQB distances.
      I hand-load mine; was using the 69 grain Match King with Varget or H335 powder – but the recommended loads didn’t get muzzle v. greater than about 2600 fps. I tried similar Noslers, and their accuracy recommendation calls for A2230 powder (23.5 grains; max load) which moves that heavier bullet at almost 3k fps. For accuracy, I’ve achieved 1 MOA at 300 yards out of a 20 inch, 1:9 twist Bushmaster barrel. This was a three-inch group from a bench at 300 – the accuracy we needed in Afghanistan, and couldn’t get with issue ammo. My wife’s M&P-15 with 16 inch barrel (1:8 twist) gets almost the same: I was looking for both greater accuracy and greater “smack” and achieved both – though nothing’s perfect. (I’d like to try Grendel, but cost is currently prohibitive, especially to build ammo stocks.)

      Just to add to the conversation.
      And, Semper Fi TV! (USMC 1970-74) (Near Castle Rock, WA) (Qualified w/M14 @ MCRD San Diego in 1970; carried M16A1, -A2, then most recently M4 ever after)

      Something else to be considered.

      1. @Mike Settles

        The heavy bullet theory for the 5.56 has been looked into before, particularly the 75 and 77gr loads. Results have been so-so.

        While I love the 300 blackout, its designed purpose was to replace submachine guns, increase modularity, reduce training, and improve logistics. It was not meant for a front line battle rifle, it is purpose driven. Meanwhile, the 6.8SPC is an ideal cartridge and a perfect performance envelope, but to effectively use it would require a new rifle built around the chambering itself. Not something a country twenty trillion dollars in debt can realistically look at.

        I think, my opinion being what it is, that the best option if the Military seeks to keep its current weapon roster while improving performance then the best option for a chamber upgrade would be the .277 Wolverine. Advances with the 6.8 means new bullets are being made in that caliber that could be furthered. The cartridge uses modified 5.56 brass, meaning switching production would not require new machining for ammunition. It mates perfectly with the modular weapons platforms like the M16/M4 and The 249SAW through no more than a simple barrel change. Its performance envelope comes to within 90% of the 6.8, and has more range than the 300AAC BLK. And, the round has a bit of historical value as it hearkens back to when the Military was looking at the .276 Pederson.

        Just my two cents.

    9. There are thousands of aluminum alloys. Pure aluminum is highly resistant because the top layer of molecules oxidize and protect the metal from further corrosion. Some alloys do corrode more because some of the metals in the alloy. Steel cases rust and must be protected by plating, painting or waxing.
      I think that BLASER Aluminum cases have a sound track record. Brass is expensive and brass corrodes too. Brass is also heavy. Brass and copper were the best for drawing cartridge cases from 1860 to 1940. Then steel was used because brass and copper [ copper being te primary metal] was a valuable war commodity for wire and electronics.

    10. I know that the guns and ammo are heavy, but I’ll stay with my .30-06 and .308s.
      I know that when you hit something with either one of those rounds, it stays down especially at the distances we have to play with today.
      Those rounds will go through most doors and walls.
      For close in work, from experience, I prefer a 12 gauge!
      End of story!

      1. ditto!
        i’m hoping for the switch to be 6.8spc, even tho they already looked it over before this decision came up
        of all the ar15 compatible cartridges I’ve tried it seems to be the best for putting down 100-150lb+ bambi beyond 300 yards, no tracking is friggin sweet! especially body shooting em on kill permits, when you are shooting 2-7 a night

      1. 25/45 first non 223/556 ar15 cartridge I tried on kill permit, 2nd was 277 wolverine and so on, I went thru 7 different cartridges before settling on the 6.8spc for high volume bambi and I hope DOD does too and for the same reasons!

    11. I’m guessing that the choice will come down to cost, The green eyeshades types will militate for anything that costs less. That’s the death knell for 7.62 NATO or 6.5 Creedmore as neither round is compatible with the M4 sized lower receiver. I’m partial to .30 caliber, so, if it’s suitably powerful or can be made so, I lean toward .300 Blackout. Besides requiring only a barrel change, the round is compatible with the billions of magazines already owned by the armed forces. And since it uses an enlarged .223 case, there’s no loss of magazine capacity.

      1. The 300 Blackout is 7.62×35 and the .221 Fireball is the parent case. Powder charges are limited by case volume. The .223/5.56×45 will hold about 40% MORE powder by volume.
        The 300 BLK is a short range cartridge pushed to its limits. It is in the power range of a 357 handgun.
        A 300 BLK SBR would be ideal for arming school teachers, Soldiers might need to shoot people 1/2 mile away and the 300 BLK just isn’t suitable.
        The 6.8 SPC is a Winchester 270 which is a necked down 30/06 or 7.62×63 or 6.8×63.
        A 7.62×51 NATO is a 30/06 in a 1/2 inch shorter case.
        The ideal military system would be light weight with the power of the 7.62×51. Using an aluminum case would save a lot of weight.
        Such a system would save money since aluminum is cheaper than brass and the stocks of 7.62 NATO ammunition could still be used.
        300 BLK is ideal for police, school teachers, home defense.

        1. If the parent case is 221 Fireball how come if you don’t want to buy new 300BO brass you fabricate it from 223 brass? The 200 300BO cases I bought on sale from Midway came in blister packs & have a 223 headstamp. There are several YouTube videos showing the process of turning 223 cases into 300BO cases. 1st the 223 case neck is cut off. 2nd these are resized using 300BO resizing die. 3rd the cases are trimmed to the correct length.

          1. 5.56×45 brass aka .223 Remington is cheap. Forming a case begins with shortening the case from 45 mm to 40 mm. Then it is run into a .223 full length sizing die to set the shoulder back and create the neck. The expander rod sizes the inside diameter of the neck and if te neck outside diameter is too big, the case neck is reamed or turned and the case is trimmed to 35 mm.
            Starting with commercial 221 Fireball reduces the reaming or turning. Spend a little money and save time and tooling costs.

            1. You can buy 300BO brass formed from 223 brass for less than 221 Fireball brass. If money is more valuable than time go the range brass 223/556 route. Actually if one is concerned about the possibility of case neck thickness use only 223 brass.

    12. First off, yes, it is time for a different round than what DOD is currently using. But everyone must understand what the overall intent was for using the 5.56 x 45 round. Tom Votaw is correct on everything he said, but there is one more reason the military went to 5.56; lethality. They were not trying to kill the enemy, only wound them. The premise was this: if you kill 10 fighters you take 11 out of the fight; the 10 dead and the one who stays behind to evac the bodies. If you wound 10 fighters (presumably enough to keep them from continuing to fight) you just took 20+ people out of the fight; one person for every wounded to carry them out and how ever many it takes to carry the gear from those 20 people.

      Also, the military was still stuck in the Cold War symmetrical warfare mindset when deciding to adopt that round (and really didn’t finally move on and update tactics and strategies until 2005).

      And my background was 20 years in the Navy, retired in 2013 and did four deployments after 9/11, all with Naval Special Warfare. Two in Iraq and two in the South Philippines.

      1. You are assuming that the enemy forces are inclined to evacuate the dead and wounded. In some cases, they may just leave them on the field when they withdraw or, if wounded, kill them.
        They may even think that because we are the “good guys”, we’ll pick up their wounded and dead, then “booby-trap” them.
        Not all enemy nations/forces behave according to the Geneva Convention.

      1. Yes, I think the military should adapt to this round. Being prior military myself and owning several ar’s chambered in 6.5. The Grendel shoots out flat to 3-4 hundred yards and is a good round between the 5.56 and 308. Penatration is better and the ability to carry extra ammo is key. I think this is the best AR round to date.

    13. The M14 has a switch at the rear on the receiver to select full auto or semi. The switch was removed by most commanders. The M14 has a high cyclic rate, a stock that does little to moderate recoil and muzzle rise. The M14 has a flashhider and needs a muzzle brake.
      An AR geometry is better for handling recoil. By using a heavy buffer the cyclic rate is slower and a burst or 3 shot trigger prevents the rifle firing the whole magazine in one 3 second, 20 round waste.

    14. This is an impressive amount of derp here. Thank you restoring my faith that there is still gun store, mall commando talk on the internet. And here I thought everyone believed in science. Personally, they should replace 5.56mm with the .45 ACP. in fact, everyone should be issued old stocks of 1911s and 45 ball ammo instead of rifles. We know how much more lethal it is over everything.

    15. If our military brass didn’t morph into politicians as soon as they set foot in the Pentagon, (and actually do have a good reason for the caliber requirement), they would simply procure a synthetic stocked, 19″ barreled version of the M14 chambered in either .260 Remimgton or 7mm-08 for frontline troops, and solicit bids for a SAW in the same chambering. Either can launch a 139 to 145 grain bullet at better than 2,600 FPS with less recoil than the 7.62 NATO. Issue P90’s to support personnel, and call it a day. Of course, weapons procurement has been an extremely political process since before WWII, so whatever our soldiers do eventually end up with, you can rest assured it won’t be chosen based on their needs.

    16. The DOD might choose the 6.8 SPC with all the .30 caliber brass available but the 6.5 Grendel is the better choice because it has a greater range in bullet sizes including those with better BCs than either the 6.8 SPC or the 300BLK.
      Note: Speed is not just about barrel length, its also very much about powder choice (fast v. slow burning) and bullet weight.

    17. Back in the 1930s the Garand was going to be adopted in caliber .276, General Marshall overruled the board and the Garand was adopted in .30/06 with a new load. The M1 Rifle came with the M1 ammunition with a 172 gr FMJBT. The M1 ammunition was soon replaced because National Guard rifle ranges would not contain the 172 grain bullet.
      The M2 Ball with a 150 grain FMJ Flatbase was adopted and was the standard round through WWII and Korea.
      Improvements in chemistry replaced the 1930s smokeless powder with Improved Military Rifle powders such as 4064 and 4895.
      To stay within the allowable pressure curve of the M1 Rifle the powder load was reduced, leaving about 1/2 inch of empty space in the M2 Ball ammo.
      After the Korean War the work on the M1 replacement included duplicating the ballistics of the M2 Ball in a shorter case. The 7.62×51 NATO aka .308 Winchester is just that. The T48 rifle [if I remember experimental number] was adopted as the M14. The M14 gas system does not have the weakness of the 2 foot long operating rod that is easily bent with powders slower than 4895 that make port pressures too high for the M1 to handle.
      The 6.8 SPC is a nominal 270 caliber. Making armor piercing bullets is easier with a larger diameter projectile. A tungsten steel core with a a soft lead layer under the jacket allows a heavy enough have enough mass to defeat an inch of steel armor.
      Since the Vietnam War aluminum alloys and deep drawing machines allow making cartridge cases from aluminum instead of brass saving 70% of the weight of the case increasing round count on a combat load. A more effective terminal performance might make up the difference in count between 5.56×45 and an aluminum cased 7.62×51 or even a 6.8×51 gaining 2700 – 3000 fps with a heavy enough bullet to be effective on cars and trucks, enemy wearing body armor, and ranges out to 1,000 + yards.

      1. Wouldn’t the aluminum case of a 7.62×51 for Military purposes corrode quickly given all the various climate changes and storage facilities with variable temps in them , much like the cheap Bear ammo does?

    18. If it’s any bigger cartridge it will be in a totally different weapon system, that will take them a decade and millions of our dollars to accomplish. I like the Grendel a lot and the 6.8 is no slouch but the Grendel has a ballistic advantage with better bullet design. A midsize piston AR would really thrill me!

    19. Here’s the word on what the new round may be:
      “Ideally, the Army’s rifle should fire a round between 6.5mm and 6.8mm, which is highly accurate because it retains supersonic velocity longer than existing military calibers, and it also generates less recoil so fully automatic fire is more stable, he said.”

      Here’s the word on the SAW upgrade:
      “The service plans on fielding a Next Generation Squad Automatic Rifle (NGSAR) — the first version in the Army’s Next-Generation Weapons System that chambers a round between 6.5mm and 6.8mm — as a potential replacement for its 80,000 M249 SAWs starting in fiscal 2022 rather than the original target date of fiscal 2025, Col. Geoffrey A. Norman, force development division chief at Army HQ, told Task & Purpose, with two per “nine-man infantry squad.

      1. Ditto on the Valk. People ought to try firing this round to see how much better ii is than the .223/5.56 using the same AR rifle.

        Bullet Foot Pounds of Energy at 1,000 Yards
        .223 Remington 77-grain Matchking 158 ft-lbs
        .224 Valkyrie 90-grain Matchking 402 ft-lbs

      1. @Bill, Well, it is government work, so the results will be subpar. What exactly we don’t know yet because not all of the after service offers of executive employment are not in yet. Then there is the picking of the low bidding vendor to make and supply the thing. Oh, yes, there is lots of corrupt money to still be made.

    20. Grendel has bolt problems. Type 1 or type 2 bolts. Great round though.

      No calls for the return of 45-70?……….it hasn’t gone away for a reason……..

    21. The M4 of today and the M16 of Viet Nam, where I spent my early adulthood, are different in their lethality not because of the ammo. No the M4 has a very short barrel and making it as short as it is caused a serious loss of velocity. .That loss of velocity is todays failure problem. If one had a chance to e fortunate to seethe m16 and the XM177 in combat they would see the validity of this. While the XM177 was easier to pack around , it lacked the lethality of the M16 because it gave up too much velocity If you want the M4 to be a killer, lengthen the barrel, It is that simple…All you had to do is shot the enemy, not the bushes.

      1. I like the .270. I use one for deer hunting and it has some kind of knock down power. I shot a 240 pound buck and he went down like he had been pole-axed. I shot one that was within spitting distance of my stand a couple of years ago and he never knew what hit him. He was also over 200 pounds. It is a very flat shooting round that has lots of speed.

    22. With all the girls and wimps in the military now. They will be looking at weight over firepower. I can’t carry that it’s to heavy. Oh, it hurts when I shoot it. It kicks to much. There are still a lot of good people in the military. But Clinton and Obamy pushed in queers and girls. So light with no recoil will rule the day.

    23. For starters, and disclaimer, I won’t argue with or repeat the many comments already here, youse have your beliefs, some I can hang with. (As an aside, being a now-retired former fed investigator, I wince when I see some of the horrid spelling and even minimal attempts at decent sentence structure. Even the author has to figure the difference between “break” and “brake”. P-lease, show the pinheads who lurk, and sometimes plant a turd here, that we are reasonably literate. Common sense and intelligence are already quite present here, which I appreciate, because we must outsmart the opposition, beat the faux intellectuals and arrogant but wrong “elites” at their own games. We already know we can beat them on the field, should it come to that. But let’s look a bit sharp doing it here in the meantime, OK?)

      Now, to gunfighting calibers. I have the grand luck to have a scar on my left inner arm from an M1 carbine round, courtesy of a Viet Cong shooter (the VC took weapons off dead ARVN’s back in 1966, before they all got AK’s). Anyhow, my corpsman dug the round out, powdered and wrapped the wound, and I went right back into the fray. Life as a Marine grunt. IF that had been an AK or even SKS round, it’d been medevac time, and maybe even a bad arm for life.

      We coveted our M14’s, and when the word came down about the Mattel toys, we fought tooth and nail to keep that 7.62, ammo weight and count be damned. Then, it was “issue the M16’s to the guys in the rear, officers, etc., but leave the shooters, the grunts, alone, because we are killing what we aim at with what we got”. Well, I got hit a few months later, and a ticket out on a C-130 medevac, so lost touch with my crew for a while, but read about the 5.56 round deflecting in jungle fighting, malfunctions of the rifle, and the death toll from being trapped with a locked-up M-16. Years later, at our company’s reunion, we talked over beers about this, and unanimously right up to and including our skipper, the memories of finally having to give up our M-14’s were still there.

      The rationale for this 5.56 caliber was about carry capacity, weight, and mobility. On paper, like always, it read good enough for the JCS to bite. For us, even the little guys (itty-bit’s) it didn’t, it sucked. But now, remember what our current military looks like: The females in particular. The original rationales for lighter carry, now including issues like handling recoil, once again become part of the formula. This, based upon some feedback from recently discharged Marines I’ve talked to. Field maneuvers with mixed gender units reveal some issues with handling weight, like full rucks, ammo, water, etc. Fortunately, there were no females in the grunt units in their deployments, but you know that is coming – trial by fire, not by FX.

      From this point on, I respectfully decline to comment too far, but if the pussification of our military that began under Obama has to include the actual trigger-pullers, all bets are off. Now, IF the powers (the Joint Chiefs) were to understand the need for a tiered infantry weapons system, we could hope to see something like what has worked so well in past eras. Take WWII: A Marine rifle squad had M1 Garands, at least one BAR, officers and senior NCO’s had a choice, Garand or carbine. Usually, there was a .30 cal machine gun nearby. That carried through Korea, until the early 1960’s, when the M-14 replaced the Garand (7.62 vs. 30.06), the M-60 machine gun replaced the BAR and the .30 cal. three man gun. We went into Vietnam that way, with other weaponry as well, like the M-79 grenade gun, and still carrying the old 3.5 rocket tube (my penance).

      From there, you guys know the rest of the story, up to present day. My premise for a Marine infantry squad, fighting in 21st Century locales, looks something like this:
      The riflemen, the core of a squad, should have a select-fire, medium range rifle that lands somewhere near the ballistics of these 6.5 to 7.62 calibers you guys refer to. IF the squad member cannot qualify, cannot maneuver, and cannot carry his/her complement of gear, including ammo, then someone better exercise some tough love, and spare the rest of the squad the risk, and replace that member. I don’t give a good loud fart if it’s a gender issue; it’s about the squad’s mission, and survival, first. Obama’s ghost be damned. Our SecDef Mattis needs to remember his roots, and step up on this. Warfighters must not be hamstrung by PC foolishness.

      There still needs to be a designated marksman, perhaps only needing good optics on the new issue rifle, because a DM needs to be able to bridge the role of a line grunt with a sharpshooter, out perhaps to 500 meters. Beyond that, it’s a job for the 0317’s, snipers. Then, finally, a Marine squad still needs a sustained fire auto gun, what was once called a Squad Auto Weapon (SAW). A unit needs that for fire and maneuver stuff, especially in urban turf. I don’t even know what those options are anymore, been out too long now. I don’t know dick about the Army’s needs, but it’s got to be similar.

      The newer gunfighter veterans, if any on here, know what is needed, because they walked the walk. Get hooked up with your congressmen and make some suggestions, (unless like me in deep blue Oregon, your reps are now a bunch of left-wing punks only interested in illegal immigrants and the Deep State). Then, just armor up with what you prefer, and watch what the military ends up doing. Like me. Yep, 5.56 is in my safe, just not the 55gr. fmj version (except for range day ammo). And, an old Marine grunt will never be without that 7.62, both in x51, and x39. After all, the commie round still kills (it took out a lot of my company, at least half of our 37 KIA), and the AK will rattle out rounds in a swamp or sand pile if need be. A better truck gun doesn’t exist, and that ammo is still cheap and plentiful. YMMV. Sorry for the tome.

      1. first sir, thank you for your service and insight on battlefield rounds. Everything you said is dead on, with how many rounds someone can carry is more important to the big guys in the offices not what that round can do. historically the generals in Washington have been too worried about the pennies it cost per round than how much a soldier’s life cost. I really enjoyed your comments and thank you again

        1. Donald, Tim just delivered an informative Red, White and Blue discussion with topic on several levels which included a request for intelligent exchange. He delivered on that and you counter his argument with one word that hangs you up, and on the third line no less. I’m wincing at your quote and end quote placement. Had you reached line 11, youse would have seen an offering for reasonable literacy by the author. Dad burn It Virginia, git meez a beer an finish reedin the article. It is interesting and it’s the least we can do for a guy who took a bullet. I’m not checking the box for email notification on reply so don’t expect a quick retort.

        2. Vernacular is often used in common writing on Internet posts and elsewhere. You picked one word out of 1,084 to attempt to discredit him? You couldn’t even write one grammatically correct sentence in your rebuke of his post.

        3. Donald, like the man said, it’s vernacular, a colloquialism, slang, whatever. I’m not an elitist, just a guy, so I have some fun with our language, time to time. But my original point stays – write smartly, let the “others” know we are much more than a bunch of “loons with guns”. Si?

      2. Enjoyed your comments. Thank you for your service. I’ve shot a lot as a hunter. 38 racks since 1974 is way over the average. You’ve got tons of history shooting so I’ll just add my two cents for kicks. Never cared for 5.56 for all the same reasons you covered. I want to know I dont need more than one shot and then move on to new target. On deer I use .308 win (7.62) in 150 gn BTSP. Would never go higher. If I were ever in combat and had a choice I’d go down to 100gn. I’d value your input. Not into all these new calibers you need to hunt for or order. 30.06 and .308 a pretty much identical ballistically. I chose .308. The short barreled M4 doesnt exactly trip my trigger. I’d want 4″ more. So in 100gn how much difference in carry weight would there be per day 100 ends? Wasn’t carry weight the whole reason the .308 was replaced by the 5.56? I never was in the military just ” special skill dept” in this war. But I’d feel better if I knew we have developed the ultimate weapon in an AR and that the SAW used the exact same round whatever grain bullet was chosen. You tell me. How’d troops feel about a 7.62 in 100gn?

        1. Russell, I’d have to defer to the numerous and skilled ballistics minds here. I fear that it would be a challenge to load a .308 case behind that light a bullet with the right powder and number of grains to prevent a tumbling effect somewhere along the trajectory… like the charge would overwhelm the round, but I could be way off. Worth trying.

          Nonetheless, when the serpent strikes, I’ll likely still reach for the 7.62×51, because I am old school, (even though 6.5 Creed and .300 BO youngsters reside next to it, because some of these guys like ’em so much I couldn’t resist). IF I have to crawl in the bushes, maybe the AK goes along; Charlie did OK with it, I recall. Got something for nearly everyone…

          Back to lurking. I’ve caused enough consternation and distress for now…

          1. The 200+ grain 300 BO subsonic are ideal for building clearing operations in urban environments with suppressed select fire SBR’s. This combo is the best means to minimize hearing loss of our warfighters. When I was young & dumb I suffered permanent hearing loss burning through 2 ammo cans shooting up the rats at the Cu Chi garbage dump w/my issued M16 on auto mode. Couldn’t hardly hear for a week.

      3. Old Marine >>> Timothy Votaw
        I love it. My sediment exactly. I have more faith in a fire team than in any other unit in any military. the four man Fire team has built the croch’s reputation all thru Marine history and always with good f. ire power. In all the wars that firearms were used, the heavy caliber has always won out If you don’t think so then you’ve never seen a Ma-Duce in action. Overwhelming Fire power is what wins, not how light the load is for the shooter. Artillery and Mortars are just big guns with a bigger bullet. this true thru all of history even with edge weapons. Shooting skills are 50% of any firefight so training is just as important as the weapon you use. Gladiators in old Rome knew this and trained constantly. It’s not the weapon you use as much as the skill with which you use it. Enough said … If it throws lead it’s good enough if you are good with it. I thank you timothy for a goo realistic evaluation of the weapon situation. >>> Oldmarine

    Leave a Comment 250 Comments