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Next Post offers a sneak peak at an experimental rifle with enough picatinny railage to hang all of your Christmas ornaments. The Taiwanese AR-style  XT100 is chambered in 6.8 SPC caliber. Our esteemed colleague reckons “6.8 SPC is slowly gaining acceptance outside of the United States, where sadly it has not been adopted by the special or conventional forces.” While Sharp As A Marble’s a big fan, and the rabbi’s go-to gun is chambered in 6.8 SPC, the cartridge is about as popular as that guy in high school who mastered COBOL. Who went on to make millions. Does 6.8 SPC have what it takes for a come-from-behind victory over ARs chambered in panty-waist .223 (5.56)? Just kidding. I heart my FN SCAR. But do you heart 6.8 SPC?

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  1. The problem with 5.56 is that it won’t defeat cover. That being said unless Russia, China, or the USA adopts 6.8 I probably won’t get a rifle chambered for it.

    Does anyone know how much 10×30 mags of 6.8 weighs vs. 5.56 or 7.62×39? It is not hard to find ballistics comparisons but I can’t seem to find cartridge weight.

    • Loaded magazine weight is higher because all 6.8 SPC magazines are steel (at this time). It’s not really a fair comparison. We’d get lighter magazines built if the military were to actually adopt the round for general use, which would help to close the gap. Of course, the round is heavier on its own; so carrying the same number of rounds would still weigh more … I haven’t got a precision scale to compare M855 to my 6.8 rounds.

    • How often do you need to “defeat cover”? Just curious. It seems to me that the extra cost of the 6.8 would not be worth it unless your job involves shooting “bad guys” (military term!).

  2. I like it. But I’ll never own an AR chambered in 6.8 unless someone like the Army adopts it on a large enough scale to allow me to shoot alot of it relatively cheaply, which probably won’t ever happen.

    ‘Til then, 5.56 for me!

    • I’ve actually got one. I bought the Barrett Rec7 when it first hit the scene. I love the rifle … But it is a safe queen at this point. It’s just too expensive to shoot. I keep a couple cases of ammo in reserve, but otherwise it is sitting in the safe waiting to be called on for some range time. It’s going to be waiting for a while, I think.

  3. I have a 6.8mm AR for deer, sihlouettes, and whatever else I am allowed to legally shoot. It is about as much recoil as I want in a medium round.

    The selling point of 6.8mm is that the AR lowers work with the 6.8mm uppers. The bullets are similiar (though not identical) in length so most of what we have on hand can be kept.

    I don’t think the US military is going to change to a new bullet. There is just too much involved. Magazines (and other components), new range and training support equipment, publications, training (new recruits and all existing personnel), inventory replacement…. The list could be near endless. The M249 is also a 5.56mm weapon and what do we do with it?

    I wish that the US military embraced the concept that it is a martial force. Shooting is its business. Having served in various roles since the M16A1, in my opinion it does not. It has a training program for shooting. But that is not the same thing. Our soldiers are more than willing to customize their weapons and accessories. A good many would even purchase their own weapons if allowed to carry on missions. Think how many soldiers would purchase a sidearm if allowed by regulation.

    Suppyling bullets is not a challenge. Getting the US military to embrace the culture of shooting is. Change that and you will see insurgents dropping like flies (with really big holes in their chests).

      • Just dropped a feral pig with my 6.8 this week.
        Took one shot.

        Two of my friends needed two shots for their pigs, and put a 3rd in them just to be safe.

        (They were using 77gr, I was using 110 gr.)

        Just saying…

  4. Aside from ammo costs (Silver State being effectively a single source) which makes reloading practically a must, I like 6.8spc. More ballistic energy and easier to suppress. A LMT MRP with 6.8 barrel and bolt makes it easy to switch between 6.8 and 5.5.6 on a single rifle. I’m not a hunter, but also gets around some of the < 6mm game restrictions in certain areas.

    Another arrow in the quiver..

    • SSA is not a single source for the ammo. I’ve bought Remington and Hornady loads, and I know Sellier & Bellot also loads 6.8 SPC. They all shoot well, and there isn’t a significant risk of getting a bad batch of high-pressure ammo as SSA has been known to put out from time to time. (SSA loads the military ammo, so they have normal and “combat” loads. The “combat” loads should be safe for SPEC-II chambers, but there have been several documented cases of these being loaded too hot.)

  5. Personally, I have a thing for magpul’s polymer magazines; they aren’t coming out with dedicated 6.8 mags, so I’m not interested in that caliber.

    .300 blk on the other hand is right at the top of my list.

    • .300 Blackout is a great alternative caliber if you run supressed and don’t have a need or desire to extend range beyond 200 yards. The .300 Blackout was intended to be loaded for subsonic speeds; so you’ve got some limitations there. I reckon it hits pretty hard though.

      • With a 16″ barrel the 125gr 300 AAC Blackout (7.62x35mm) has 1,405 ft-lbf of muzzle energy, velocity is 2,250 ft/s. The specs for the subsonic, 220gr round are 498 ft-lbf* at 1,010 ft/s. With a 16″ barrel a 115gr 6.8mm SPC (6.8x43mm) has 1,694 ft-lbf of muzzle energy, velocity is 2,575 ft/s.

        There are advantages to both rounds. I like how the 300 Blackout is designed to feed from standard 5.56mm magazines without any modifications. 6.8 SPC requires it’s own magazines. However, I definitely think the 6.8 SPC is a much better replacement for 5.56mm NATO. It has very similar ballistics. It’s accurate out to the 500m mark, which is probably the maximum effective range of the catridge. Sure you can shoot 5.56mm out that far, but it’s not particularly lethal at those ranges. It’s lethality drops off rapidly once it’s velocity drops below 2,700 ft/s when utilizing M193 or M855 ammunition.

        *That doesn’t sound particularly impressive until you start thinking about the kinetic energy of the current standard for suppressed entry weapons, the MP5SD. Subsonic 9x19mm likely has less than half the kinetic energy of a 220gr 300 Blackout cartridge.

  6. I know that the rabbi loves this round so I can’t just dismiss it out of hand. Buh-ut, since we already have both the 5.56 and the 7.62 Nato rounds to choose from and neither costs and arm and a leg, and there are plenty of AR-10s and -15s to choose from (not to mention traditional-style rifles in .223 and .308), I don’t see much of a future or a need for the 6.8 SPC.

  7. I will soon purchase a 6.8 upper for my Rock River Coyote Carbine. For the price of an upper coupled with the fact that I’m a reloader, I figure WTH? It’s one more toy in my box. I certainly don’t NEED it, but I want it and that’s the best justification of all.

  8. I like the 6.8 as a concept, and I think it provides a useful upgrade in power.

    But I agree with the commenters who feel that the cartridge isn’t popular enough to practice with it economically.

  9. As to 7.62x51mm NATO AR-type rifles, they’re pigs. Unloaded a 16″ SR-25 pattern rifle weighs in at around 9.5lbs. Throw in the weight of carrying a battle load of 7.62 NATO and you’ve got a guy who is seriously weighed down. Not to mention the recoil is very high, nearly twice the numbers for 6.8 SPC. I’d love to have an SR-25 EMC, Colt’s forthcoming SP901, or LWRC’s REPR, but they just don’t look that appealing next to a SCAR-17s excepting magazine availability.

    • If I were an infantryman going into battle I’d agree that the 5.56 is a better weapon for the majority of the squad. The 6.8 is, at best, a marginal improvement over that. Nice, if you can afford the luxury, at this time Uncle Sam clearly cannot.

      But I’m not going into battle, nor do I have a squad. More often then not I have me, and not much else. In such cases I want any hit to offer maximum stopping potential. If the contents of one magazine (maybe two – tops) will not suffice then neither will an entire battle load.

      Make mine 7.62×51.

      • Im a former soldier that’s been in battle. I wish I had the 6.8 when I was there as we’ll as the guys there now. The round was designed to fix or overcome the .223/5.56 deficiencies yet uncle Sam won’t get off his but and equip the guys on the line with the proper tools. We wear body armor that is heavy an brittle when the market has light buoyant and non brittle available. Yes buoyant, fly over water or travel through it to the mission and see if anchor or floatation is what you would like to wear? Hope I don’t sound like im ranting just my .02 worth

  10. The 6.8 SPC is basically, a .270 Lite. It was developed to be used as a short barreled Rifle. It’s does great with a 16″ barrel. Mag weight. Look at the hit to kill ratio of the 5.56 vs 6.8SPC (40% more energy). Double tap was created for a reason. All you need is a barrel, bolt & mags to convert (same lower). Wilson Combat Ammo are 2700fps out of a SPC II 16: barrel. Oh, Tula & PCP are coming out later this year.That ought to bring cost down. If you want a deer, yote & hog round out to 300-400yrds (Even Elk has been killed out to 372yrds.) out of a AR 15 platform, then 6.8 is a great round!

  11. Nothing and I mean nothing will replace good shot placement.

    I have an AR-10 in 16inch with 25 round mags (reason of going to armalite in the first place), with the right ammo that thing is a beast.

    I bought a LWRC M6A2 16 inch barrel chambered in 5.56 (I also have the 8inch 6.8 spc PSD upper for it as well as the AAC 9inch .300blackout upper).

    So four calibers there all have strengths and weaknesses. If your talking home defense then I go with none of them. I would go with a Sig 229 in .357 (since I carry it for work) and I would go with an 870 shotgun, because a shotgun is just intimidating.

    the above calibers are this.

    End of the world as we know it event.
    5.56 all the way. It is so common and easy to find.

    Aliens like in falling skies
    7.62X51 in my AR-10 because when it is time to hit hard it is time to hit hard.

    6.8 PSD running and gunning with full support and supply convoys it hits harder than the .300blackout and the 8inch barrel is good to 300 meters.

    .300 blackout specialized quiet operation.


    Mp5 and twin Sig 229’s (work again has me trained so well) but chambered in 9mm.

    since all 3 weapons carry the same round and zombies are just head shots makes sense.

    but honestly I wish the US Government would adopt the 6.8spc soldier would benefit from it. However I stress shot placement shot placement. All we do at work is head shots. granted we work mostly at 7 yards but still it is a good concept.

  12. I’ve got a Bushmaster 6.8spc and i love it. its got a little extra kick than 5.56. I use steel 5.56 mags for my 6.8 ammo and it fits perfectly, no problems or jams. it only fits 26 rounds as opposed to 30 rounds of the 5.56. I dont really notice a difference in weight between the two.

  13. I own two AR’s in 6.8 SPC. A 16″ Stag Arms and a 20″ RRA upper on a Delton Lower. The 16″ has accounted for three deer. All one shot kills, one close, the other two around 200 yards. I hunt in the north where the deer average 200
    pounds plus once gutted. The biggest of the three was an eight point that scored
    around 140 inches and I estimated at 4 yrs old. The 20″ was purchased with the intent of adding a night vision scope for shooting varmint and especially hogs as russian boars are taking over my hunting area and I also visit Florida to shoot as many porkers as possible. The 6.8 provides a remarkable upgrade to the 5.56, I would never take a 5.56/223 hunting for anything over 50 lbs. My .223 does a lot of Coyote killing though I must admit. I can’t wait to try barnes triple shocks as all I’ve used so far are 110 grain Sierra Soft Points by SSA.

  14. I love my 6.8! Shoot my buddy 5.56 a lot and it can’t hold up to my 6.8. I reload them and that made the round that much better. Factory rounds are expensive and not as good as the reloads. Get an AR chambered in 6.8 and you’ll love it.

  15. The only down side ive seen to the six eight is that after about 400 yds it drops like a rock. With that being said it is essentially a .270 rnd on a 5.56 cartridge it hits like a tank.Ive dropped countless deer and two moose with mine. I wouldnt trade Iit for anything. However I keep a 5.56 upper for range and coyote shooting because six eight ammo can be a little pricey.

  16. The 6.8 spc is definitely an upgrade to the 5.56 cartridge. In the M16/AR15/M4 lower receiver the dimension of the magazine well limits the length of the cartridge. The US Military as well as tactical units of police depts. across the US need a new lower receiver that will allow for a more powerful cartridge for duty. The 6.8 is a step up and offers much more power for the existing AR/M4 rifle. Personally I believe the 270 bullet is too big for the 6.8 casing thus doesn’t allow the 6.8 bullet to reach the fps really needed to be an awesome duty round. Being a reloader I honestly think someone needs to mill and design a new lower receiver to accommodate a new military cartridge that will dominate the battlefield while allowing soldiers to carry hundreds of rounds with them. I have always liked a 6.2(243 cal) or a 6.5mm bullet fired from a 47 or 48mm (in length) casing at least the diameter of the 30 Remington casing. Ideally a 6.2 or 6.5mm bullet travelling at 3000 to 3500 fps with an effective range of 800 yards and super accurate. This cartridge will be light enough to carry plenty of ammo but lighter than the current 308 ammo. The cartridge needs to be thinner and longer than the 6.5 Grendal so it will stack more efficiently in a 15 to 30 round magazine. A new cartridge that reloaders are playing with is the 6mm Hagar, a 6.2mm bullet fired from the 6.8 casing. This bullet is better sized to get better 3000fps velocity out of the 6.8 casing. I believe it is a better cartridge than the 6.8spc. Hornady is currently making the brass and all 243cal bullets can be used for this cartridge but no one is commercially making this ammo YET.

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