The Remington 6.8 SPC Round: An Up Close & Personal Look

Tom Mchale impression of the Remington 6.8 SPC Ammunition round.

The Remington 6.8 SPC Ammo
Rock River Arms LAR 6.8 Remington SPC CAR A4: It looks like a standard AR rifle, but with bigger bullets.

Tom McHale, Author of Insanely Practical Guide Books

USA –-(Ammoland.com)- I love the AR platform. And yes, it is a platform as it's a design model that allows of near infinite customization.

You can add accessories until your rifle looks like a Pakistani Jingle Truck. More importantly, since the rifle is a platform, you can obtain or build one in a dozen or more different calibers.

One of my favorites is Remington 6.8 SPC. Originally developed as a possible replacement for the 5.56mm by some folks from the U.S. Army Marksmanship Unit, United States Special Operations Command and Remington, the 6.8 cartridge is partially compatible with the standard AR platform.

Like 300 AAC Blackout, the 6.8 SPC ammo was developed in response to complaints about stopping power of the 5.56 mm cartridge, especially when used with shorter barrel rifles. It splits the difference (more or less) between 5.56 mm and .308 while still allowing larger capacity due to case size and lighter weight. As a rough example, think of a standard size AR magazine holding 25 rounds of 6.8 SPC instead of 30 rounds of 5.56 mm. Not a bad tradeoff for the extra oomph you get from each cartridge.

The energy of the “standard” 115 grain projectile traveling at 2,640 feet per second is 1,785 foot-pounds – significantly more than the 1,281 foot-pounds of a 55 grain .223 Remington bullet moving at 3,240 feet per second.

While we’re comparing energy levels, let’s look at some other “similar use” cartridges.

  • 5.56x45mm SS109 62-grain: 3,100 fps, 1,303 foot-pounds
  • .300 AAC Blackout 125-grain: 2,215 fps, 1,361 foot-pounds
  • .308 Winchester, 150-grain: 2,850 fps, 2,704 foot-pounds
  • .30-30 Winchester, 150 grain: 2,300 fps, 1,761 foot-pounds
  • 7.62x39mm (Soviet), 123 grain: 2,435 fps, 1,619 foot-pounds
  • .270 Winchester, 130 grain: 3,160 fps, 2,881 foot-pounds

Cartridge length was limited to be compatible with existing magazines, but specific 6.8 mags have been developed for better reliability and allowance for slightly longer cartridges if desired.

According to The folks at Sierra Bullets, “With the magazine length of the AR at 2.260″, cartridge length was critical. There are now magazines on the market designed specifically for the 6.8 mm SPC to allow them to be loaded out to 2.315.”

The 6.8 Remington SPC is based on a .30 Remington cartridge case, but fires, you guessed it, a 7.035 mm projectile. If you don’t recognize 7.035 caliber, that’s just the metric measurement of the popular .270 which is actually .277 inches diameter. See, there's that goofy tendency to name cartridges something different from their actual diameter again. Just like a .38 Special being .357 caliber.

In simple terms, think of the 6.8 Remington SPC as a .270 Winchester with a smaller cartridge case and less powder capacity that can be fired in an AR type rifle with correct barrel and bolt.

The interesting thing about 6.8 Remington SPC is the terminal performance down range. With about 200 feet per second more velocity than that famous AK-47 round, it has reach out and touch someone performance out to about 500 yards.

The cartridge case is based on the .30 Remington, which explains the need for a bolt swap when converting a standard AR rifle. Similar to development of 300 Blackout from .223 Remington cases, the 6.8 takes a shortened .30 Remington case and necks it down for the .277 inch bullet.

The beauty of this caliber is increased diameter and bullet weight over .223 Remington, while maintaining big time velocity from an AR platform with its overall cartridge length limitations.

Cartridge Options

I found it easy to develop exceptionally accurate loads like this 115 grain Sierra MatchKing option.
I found it easy to develop exceptionally accurate loads like this 115 grain Sierra MatchKing option.

I’ve done a fair bit of reloading and tinkering with 6.8 Remington SPC with stellar results when the right bullet / powder combination is used. While you’ll have to buy 6.8 brass (or make your own from .30 Remington.) .270 projectiles are easy to find even in these times of component shortages.

The 6.8 Remington SPC sweet spot calls for bullets in the 110 grain weight range, although I loaded a variety from 90 grains to 130 grains.

Looking at the spectrum of commonly available commercial rounds, you’ll see offerings in the 110 to 115 grain range at velocities of 2,570 to 2,625 feet per second.

Accuracy and velocity samples

Using only one factory rifle, I can’t really make a definitive statement about accuracy of the cartridge, but I can say, that with the test rifle I used, it was very easy to develop sub-minute of angle loads.

I’ve been using a Rock River Arms LAR 6.8 Remington SPC CAR A4 with a few upgrades, but still equipped with the standard RRA two-stage trigger. I mounted a Weaver Tactical 1-5x optic with a CIRT reticle and used that for all accuracy testing. Velocity was clocked with a Shooting Chrony Beta Master placed 15 feet down range. I used a Blackhawk! Sportster Titan III two part rest so I could get good stability without losing the “feel” of shooting the rifle.

At the light end of the bullet weight spectrum, I tried the Sierra 90 grain Varminter hollow point. With the right dose of IMR 4227 powder, I clocked velocity at an average of 2,546 feet per second. With this load I was able to get consistent 3 shot groups of well less than an inch at 100 yards, with the average being about .87 inches. That’s pretty impressive from a factory AR rifle.

6.8 Remington SPC makes a great hunting cartridge too. This 5 round magazine lowers the profile a bit.
6.8 Remington SPC makes a great hunting cartridge too. This 5 round magazine lowers the profile a bit.

Moving up to slightly heavier stuff, I then loaded some 110 grain Hornady V-MAX rounds with H322 powder. Average velocity was 2,451 feet per second. In the excitement of the moment, I forgot to record the 100 yard group sizes, but my notes indicate that it was “crazy accurate.”

In my highly scientific terminology, this translates to less than one inch groups at 100 yards.

If you’re into accu-plinking, get yourself some 115 grain Sierra MatchKings in .277 diameter. I developed a number of loads using these projectiles with IMR 4895 and H322. Groups with different powder and charge combinations yielded results ranging from a best of .58 inches at 100 yards using H322 to 1.02 inches using an IMR 4895 load. Velocities of the 115 grain projectile loads ranged from 2,165 to 2,249 feet per second.

If you’re more into budget plinking, you can order some pulled bullets, readily available in .270 (6.8 SPC) caliber in the 130 grain range. Even using very inexpensive bullets, abused by some sort of violent bullet yanking process, yielded groups in the 1.3 inch range at 100 yards.

Closing thoughts on the Remington 6.8 SPC

At first I wasn’t sure exactly what got me so fired about the 6.8 Remington SPC cartridge. After some use, and some deep thought, I think it boils down to three things.

I like the power level compared to .223 Remington or 5.56 mm. Whatever your preference for home defense, .223 / 5.56 has limitations if you want to hunt. Whether you buy or reload your own, 6.8 Remington SPC opens up a whole new world of hunting possibilities. Deer, hogs, or containers of Tannerite – whatever floats your boat.

Next, you can suppress it with a commonly available .308 silencer. I just mounted a SilencerCo Specwar 762 on the Rock River Arms rifle mentioned in this article and it works like a champ. I ordered a second muzzle brake so I can instantly move my Specwar 762 from a 300 Blackout rifle to the 6.8 Remington SPC. Obviously 6.8 SPC is only a supersonic round, but the suppressor really makes a difference at the firing line.

The last reason this round got my attention became apparent during the “I can’t find bullets” scare of 2013. .270 is a common hunting caliber, and generally ignored by the tactical crowd. While suitable 5.56 mm and 300 Blackout projectiles were in scarce supply, I never had a problem getting as many .270 / 6.8 SPC bullets as I wanted.

Neat stuff. It’s a fun, accurate and low-recoil cartridge with a whole lot of flexibility.

About

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+FacebookTwitter and Pinterest.

  • 26 thoughts on “The Remington 6.8 SPC Round: An Up Close & Personal Look

    1. my opinion only, I always felt from the very beginning when they first brought out the 5.56 it should have been .243. another gov boondoogle, much better choices of bullets , 308 based, unfortunately hornady has seen fit to discontinue my favorite deer bullet the 2455. always thought all of the early problems with the 5.56 in Vietnam would have been avoided and had a longer range weapon as well.

      1. Though I have only lately come to appreciate the AR, I can see how a bit more “potent” round would have served our military much better in Nam.
        I took 2 deer and 4 feral hogs this fall. All with AR platform rifles.
        One deer was taken with an AR10 in .308 Win.
        Oddly, all tour of the hogs and a very nice doe fell to and AR25 in six8. All four hogs were 200+ pounds. Three were taken with handloaded Sierra 90 gr HP. One hog and the doe fell to a Hornady 110 gr V-Max.
        The six8 is quickly becoming one of my favorite rounds. I’ll build another 5.56/.223, just because of their popularity.

      1. My AR10 in .308 Win tips the scale at 11 pounds with a full 20 round mag.
        My AR15 in six8 at a much more comfortable 8+ pounds.
        The AR10 upper long enough to handle a .270 length case along with a bigger BCG and heavier buffer, I fear would push the weight up around the 15 pound mark.
        If one MUST have a semi auto .270 Win, there is The BAR and the Remington 74 series….or a six8 in an AR.

        1. Just measured a round I loaded for my Ruger No.1 .270 Winchester. It’s 3.242″.
          A handload (Sierra 90gr HP) for my AR six8 measures 2.265″.
          The six8 is the shortest .277 round on the market.
          To me, the six8 is just about the “perfect” AR15 round.
          The six8 is far more effective down range than the 5.56 and it has a far more effective range than the .300 Blackout.

    2. I would prefer a rifle in 30 RAR, but Remington has abandoned it and its fans. Unfortunately 30 rar requires a whole caliber specific upper and magazines. And Remington was the only company to make the ammunition which was difficult to buy. They stopped making the rifles and uppers several years ago and the ammunition is drying up. 30 RAR (30 Remington AR) is really specific to medium game hunting and the Remington magazine only holds 4 rounds (deer don’t shoot back).

    3. I just received my Barnes 95 grain ttsx bullets in the mail today. I will most likely use AA2200 for my powder choice. Last weekend my girlfriend shot a doe, one shot kill, and a buck, one shot kill with my 6.5 Grendle M4. She shot a doe and a Buck with her .300 Blackout last year. using an AR M4 for that.

    4. The 6×8 was in guns and ammo, August 2004 page 72-77. On same page, it violates the Hague Act 1907. Prohibits using ammo that could cause indo suffering. Now page 74. When fired into ballistic gelatin frags into 10 to 15 parts WOW.for the special forces. Military -FBI -Law enforcement, make the bad guys really scream.

      1. I haven’t read the article you referenced but the 6.8 cartridge in of itself does not violate the Hague Act of 1907. The use of bullets designed to flatten or expand easily (often referred to as “dum dum” bullets) are what were banned. As I understand it, the U.S. didn’t ratify (agree to) these stipulations. We as a military typically use full metal jacket bullet that are not designed to flatten or easily expand. However, we do have missions/mission sets that require the use of expanding bullets and as such, the U.S. accepts responsibility for the use of the rounds.

    5. The 6.8 is a great cartridge I have built 2 myself Wilson combat barrel and ar performance
      I would highly suggest ar performance in my opinion. It’s a better barrel and alot cheaper. Using 95 grain Barnes ttsx bullets elevates this cartridge to the next level. Aa2200 powder is the way to go for velocity while h322 gets a little tighter grouping. This is the way to go if you want to hunt with an ar-15. Aa2200 loaded with 30 grains coal at 2.295 is the sweet spot
      Pri or asc mags are good to go for that extra needed length

      1. I have built 2, a Daniel Defense 18″, a 16″ ARP. From groundhogs to whitetails, they both kill equally dead but the ARP wouldn’t cycle w/o opening the port even with very warm loads. And the bolt and extension was a bit too tight (needed polishing). Sure, ARP is adequate field grade but nothing I could do would via hand loading/tweaking (experienced at building and loading both) could match the 16″ ARP to the 18″ DD. Basically, (my observations) the DD could do at 200 what the ARP could manage at 100. Ceteris paribus, all things equally terminated, just one more barrel clearly more accurate (longer, faster, heavier) that the other. Hornady 120 SSTs

        120 SSTs: 2490 fps/2445 fps using the same charge of AA2200 different days, time temps. in the DD/ARP
        XM68GD: 2914 fps/2838 fps DD/ARP (the Gold Dot at 200 yards almost penetrated 1/4″ plate steel.)

        Now why 6.8? the APR rig less than 7.5lbs w/strap, Nikon 3-9×40, MI 1st gen clone 15″ free float, M4 BS, simple 3-prong FH, generic BCG, Anderson Upper & Lower.

        (No. 3 with a Bison Armory is next.)

    6. If you are building an AR15 in 6.8 SPC you need to get the best 6.8 barrel from AR Performance, 16″ 11.25 twist 5R. Its the best barrel for the 6.8.

    7. Looking at pulled bullets and the lightest I see is 135 grain. I know the sweet spot round is 110 grain and saw the author loaded up to 130 grain but never mentioned anything further. My reloading magazine & books only go as high as 115 gr in 6.8 SPC and the 270 section starts at 90 grain up to 180 grain which of course I wouldn’t do but what is the max grain weight bullet that should be loaded for the 6.8 SPC?,
      I’m very new to this so any comments would be appreciated or e-mail me at ( [email protected] )
      Thanx guys

    8. This deer season I used a custom (home built) 6.8 SPC.
      My load was the 110 gr. Sierra Pro Hunter and H335. My 8 point buck dropped from 1 round at 175 yards. Never took a step. Just straight down. The entry hole was barely visible and the exit was about the size of a half dollar. Minimal damage to edible components but tremendous blood loss. The lung on the off side was destroyed. All my friends didn’t think I’d have success with the 6.8. The rifle and the round performed flawlessly. Also, the accuracy was great. Sub MOA group are the norm and I have a few in the 5/8″ range. VERY pleased.

    9. I am reloading 6.8 for my stag piston driven. Factory loads recylel prefect.My reloads stay in mag, after fired round ejectes.I.m I swing Hornsby 120 sst with HA4198 powder.28 grains. Seams like I don’t have enough gas to push bolt back far enough to pick up new round.CASES are all to specks.Gun is clean and oiled.Can I go up with more powder. May be 28.1 grains. Tried everything don’t know what else to do. Thanks Ed.

      1. Noting your post is over a year old, you probably solved your problem. When I built my 6.8 AR it would no cycle reliably. I cut 3/4 of a winding off of the buffer spring and it hasn’t missed a lick since with factory ammo. That said, I am trying to reload 130 grain pills and I get a 95% failure rate on cycling the next round. Any ideas?

        1. Though I have a safe full of blued steel and walnut, I went all out mag phos and plastic for deer this year.
          First up was a PSA PA10 in .308 Win.
          At 7:33AM opening day, it laid a nice 8 down!
          Next up was the 6.8mm Rem SPC I completed late last spring.
          It had already proven itself with about a 250 pound feral sow that wandered up under a pecan tree 60 yards from where I was picking up pecans.
          I was a bit hesitant. I’m shooting handloads with a Sierra 90 grain FBHP. My fears were unfounded! When the sear slipped, she dropped in her tracks!
          Wanting to take a doe, I drug the 6.8mm back out to the stand for the afternoon.
          Ten til 5, a 250 pound boar stepped into view at 25 yards. He dropped in his tracks to an identical Sierra 90 grain hollow point.
          When I stepped out if the blind at 5:25PM, a second feral was picking up pecans under a tree about 80 yards away. He made it about 30 yards before piling up under a deadfall.
          I’m loving my 6.8mm!
          AWESOME round!

    10. I have a Stag Arms Model 7 Hunter, with a Nikon 3x9x50 BDC scope. I have only shot at targets, but groups less than 3/4 at100 yards from bench rest. I shoot Hornady 120 grain SST bullets, will try it on hogs and deer come November. The only downfall of this rifle is that it weighs 13.75lbs. I hunt on the Pease River in North Texas and you have to be in shape to lug this rifle and pulla game cart.

    11. My son built me a AR15, 6.8mm Remington SPC with a 16″ Bison Armory 1:11″ twist barrel. I have mounted a CAA BiPod to the Midwest Indsutries handguard, with a BCA bolt carrier group and upper. The lower receiver is from Aero Precision. Optics / Sight, I am using an A.C.O.G. RCO-150, shooting 110 grain S&B stock ammo at $.66 per bullet. At 100 yds my groups are <1". I hope to be relaoding soon for $.31 per bullet. I will moe back to 200 yards on my next trip to the range. This is one fun rifle to shoot!

    12. I have been hand reloading for my lwrc for 3 years I like the 110 grain hornady I have loaded a few hundred rounds to max velocity with no problem all togather have shot a couple thousand rounds with this rifle with not 1 problem i am anal about cleaning lubng all parts after each use it seems no mater what powder i use i have used several this rifle is still very accurate at this time am using h322 very accurate at 100 yds with 110 115 gr hpbt sierra bullets

    13. Just wondering. Has anyone had any issues with the chamber area of the 6.8 barrel’s locking lugs cracking, chipping, etc since the 6.8 bolt’s diameter is larger than the 5.56’s which the AR platform was designed around?? In other words: The barrel/chamber wall thickness in the locking lug area of the 6.8 must be less than that of the 5.56. Has anyone had any issues with this?? I hear you about the cost of ammo and for non-hand loaders there’s the significant availability limitations of the 6.8 rounds too.

    14. Just for the record.
      Pakistan isn’t the only country with jingle trucks, I’ve seen then in Afghanistan as well.
      Iraq, never made it there, so no comment.

    15. I’ve been a 6.8 fan for about 3 years now. I’ve built 3 different AR’s in this caliber. I built the first one for myself for hunting whitetail and boar here in northwest Florida. After my father and some of my friends saw how effective the round was they all wanted one too. So now I’m in the process of converting two 5.56 rifles over to 6.8. I’ve been using Bison Armory barrels with excellent results. LWRC and ARP make great bolts, and PRI makes the best mags. I too shoot my 6.8 suppressed, but I use an adjustable gas block from Syrac so I don’t over work the bolt and carrier. I’ve been reloading this caliber for the past 3 years and have made a few go to loads for hunting. The 95gr Barnes TTSX with RL7 is an awesome combination. I’m getting velocities above 2800 out of 16″ barrels and shooting <1" groups. This caliber has it all; small size, good range, hard hitting, accurate, and soft recoil. My next project is to try and build a bolt action 6.8 youth rifle for my boys to hunt with.

      1. I am interested in building an AR-15 in the .30 Remington AR caliber. Would you furnish me your thoughts on the best components to acquire in order to construct
        such a rifle. My shooting range will be 100 to 200 yards.

    16. I love my 6.8. I put a Stagarms 6.8 on a S&W lower with a Trijicon 1X4 scope, American Gold trigger and it’s a tack driver. I haven’t gotten into the technical of what it’s doing like you have but the recoil is hardly above 5.56 and at 200 yds it is wicked accurate. I was going to plant it out to 300 but it was so damn hot that day I just couldn’t stand being out in it any longer.

      The only downside is the price of ammo since I don’t reload. Cheapest I’ve found for PMC 110gr is $.86 per round. But you know what? I don’t care! It’s such a great round I’ll just buy in bulk when it’s on sale and I’ll bet that in time it’ll come down.

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