Home Forums Hunting & Shooting Ask The Gunwriters 6.8 SPC

That's not true either. There's a whole slew of cartridges developed specifically for the AR besides 6.8 SPC... 6.5 Grendel, .264 LBC, .450 Bushmaster, .458 SOCOM, .50 Beowulf, and probably many others I'm not thinking about. They were developed to provide additional capabilities while still working within the physical size limitations of the AR15 operating envelope. All of these rounds can obviously be used in other action types, but there's really no point because you'd be giving up performance in other actions free of the AR's cartridge size constraints, and there are much better rounds to choose from. Yes, the .30-06 was originally developed for the 03 Springfield, but it cannot be used in all other action types because of its length; the AR family being a good example. Just as pistols involve making concessions in cartridge OAL, case capacity, and performance vs. rifle cartridges, choosing any firearm class always involves one compromise or another. Just as .40 S&W is a pistol cartridge, 6.8 SPC is an AR cartridge, and within their intended use and limitations, both work well.

None of the above named cartridges could be called a commercial success, could they. The "SPC" does stand for something. I know why it was developed, to complement the AR platform. Your comparison reminds one of the .35 Whelen or the .270, cartridges developed from the parent round not rounds developed for the 03 rifle itself. Don't know what the 6.8 will spawn.

Given that the AR platform is over 50 years old and is, itself, getting a long in the tooth, I would think all that development could go to a platform a little more forward-looking.

The 6.8SPC didnt last long in a bolt action, but I think
in an AR it will be around for awhile.

It never was intended for bolt actions. I think Remington chambered it for a short time just for kicks, but something like .260 or 7-08 makes infinitely more sense in a bolt gun.

In the AR, most of those have had some degree of commercial success. The 6.8 has been more successful than all but the .223. It has only been commercialized since 2004. "SPC" stands for "special purpose cartridge." It was developed specifically for the M16 (for use by the US Army Special Forces) from the .30 Rem case, not a modification of another existing AR case. The whole reason for its development is because the Army wanted something that provided more lethality than the 5.56 that would still work in the existing M16, while still providing very close to the same magazine capacity and not much more ammo storage space. It has a larger bolt head diameter than .223 -- .422 vs. .378. It is an entirely new cartridge, not spawned from the 5.56 case or from anything else previously used in ARs.

You obviously haven't kept up with the AR world. Despite the basic age of the design, Eugene Stoner's invention is showing no signs of slowing down. If anything, it's more popular now than it's ever been in its history. Witness companies like Remington, Ruger, and S&W getting into the AR game just in the past 5 years. The AR is here to stay well into the foreseeable future. ARs are arguably the hottest selling long guns in the firearms industry right now. It's so modular, with more aftermarket parts than any other single firearm design. There is an entire thriving industry on aftermarket parts for the AR alone. The 1911 and 10/22 are the only firearms that come close to this, and even they are in distant 2nd and 3rd place behind the AR.

If a manufacturer is developing a new cartridge for a military style semi-auto, it makes no sense to develop them for any other platform because the AR outsells everything else. It's simple, easy to work on, and easy to customize. It's gas impingement design enables it to have a higher degree of accuracy than some other semi-auto designs because there's no moving mass of parts (op rod, gas piston, etc.) surrounding the barrel during firing to impart vibrations to the barrel. It's easy to rebarrel and there are tons of match grade barrels for it. It's popular in High Power competition.

You're making the mistake trying to draw correlation between 6.8 SPC and typical bolt action rounds and in the process not giving it credit for doing what it does well. Just as .45 ACP or .40 S&W aren't well suited to bolt actions but are great defensive pistol rounds, 6.8 SPC is good for its intended purpose -- expanding the usefulness of the AR15. It is a great AR round, but AR round it is and will forever be.

and the answer is 99% nothing more! What would you shoot with a 6.8SPC that you would not shoot with a .223? Why nothing more! Deer, hogs, black bear, aardvarks, armadillos, fiddler crabs, clams, mussels ...

Nothing. Postulate as you may want to postulate and be happy with what you have, despite 300ACC, 6.8SPC, and etc. its another .223 for me, I will not emulate swampfool in which I say with the authority and certainty that the good Lord reserves for nincompoops that "this" cartridge is not good, and that one "sucks" simply that logic steers me in a certain direction over another and my needs may be different than yours!

Your claim wasn't that it could kill any animal a 6.8spc could, you claim was:

"what can the 6.8SPC do that a .223 with a 62 grain TSX cannot do"

Obviously any cartridge within a certain caliber/power range is capable of killing the same animals, but that doesn't mean that a .243Win can do everything that a .270Win can do or that a .221 Fireball can do everything a .243Win can do.

By you logic we should all hunt whitetail and lesser animals with a .221 Fireball since it is capable of such. Why go with a harder hitting cartridge?

No, the .223Rem can't do everything the 6.8spc can do. There are certainly angles and distances that a conscientious hunter might take with a 6.8spc on a deer or hog that he might not take with a .223Rem. And if the target is a human, there are types of cover at distance that a 6.8spc will punch through that a .223Rem may not, that is after all WHY it was developed.

So in the end, both will kill a 300lb hog, but if there were 50 300lb hogs in a field 300 yards off and we both got paid per head that we dropped in that field without tracking, you would be foolish to choose the .223Rem over the 6.8SPC.

That is what it WILL do better.

RifleDude has it figured out and is right on. The 6.8 gives more oomph and killing power in the AR15 platform and has a more practical and sensible reason for being than many of the scores of cartridges available in bolt rifles. It is small enough for predators but big enough for deer. I am getting a 6.5 version because I like that bore size. The AR platform in general has been and is enjoying a remarkable surge of interest-- long in the tooth or not. And that interest is well deserved. PH

The place I do most of my hunting is infested with feral hogs. Over the past 5 years, I've killed well over 150 of them. Again, where I live, hogs are pests, not considered game animals and you can kill as many as you wish, by any means you wish, anytime you wish.

I've killed them with numerous cartridges ranging from .22LR to .300 Win Mag, depending on what I happened to have with me when I happened to encounter some hogs (often when I wasn't actually hunting them). What I've discovered is that a large hog (over 300 lbs) is a very tough animal, much tougher than any deer. Some of the longest blood trails I've followed had big hogs at the end of them. I would liken them to elk in terms of toughness.

Although I've never killed them with the .224 62 or 70 TSX, my buddies and I have killed quite a few (over 30) with the .223 with various 55 gr bullets, and the results have been pretty underwhelming on hogs weighing over 200 lbs. Yes, it will kill them. For that matter, so will a .22LR... eventually. If you shoot them in the brain, it will kill them instantly. Shoulder shots are a different matter altogether. We've had many hogs run off and never found after a hit in the vitals with .223s. Although I haven't killed as many hogs with the 6.8, the terminal effects have been night and day different than the .223, with better penetration and larger wound channels. Bullets that create larger wound channels and still penetrate sufficiently kill faster. Maybe the TSX would have evened the comparison more, but the fact is, the 6.8 hits harder and penetrates better, given bullets of equal construction.

Newton's 2nd and 3rd laws of motion dictates that greater mass at a given acceleration produces greater force, and it requires more resistance to stop the motion of an object with greater mass... ergo, greater penetration. This assumes bullets of equal construction. Larger frontal diameter creates more drag and reduces penetration, but greater bullet mass allows a bullet to expand wider and still penetrate as well or better than a lighter bullet with less frontal diameter.

Since .22 centerfires are illegal to hunt big game with in many states, the .223 isn't even a consideration in some parts of the country.

If someone wishes to hunt big game with an AR15 platform, the 6.8 SPC and 6.5 Grendel will help the hunter meet legal requirements. When hunting elk or moose in Colorado, a bullet must have a minimum caliber of 6mm, a minimum energy of 1,000 foot-pounds at 100 yards and weigh at least 85 grains. 223-caliber ammunition is not permitted for big game hunting.

For military use, there is a tradeoff. While the 6.8 SPC and 6.5 Grendel have advantages in energy, these new cartridges have larger diameters, are heavier and fewer rounds can be carried in the same volume magazine or ammo box. More fire discipline may be required when carrying fewer rounds. Unless the newer cartridges provide a clear advantage, it is likely that 5.56x45mm will remain the NATO standard.

Given that a lot of guys have backed off of more powerful cartridges to stuff like the .257 BOB or 260 Rem, the 6.8 should be the bee's knees for Whitetails unless you are shooting over a soybean field or some such. I didn't get to hunt much during our short season this year, but I alternated my 6.8 with my .257 ROY. Totally different cartridges, but whatever is fun to tote. Wish I'd have even seen a deer on the four or five little hour jaunts that I got to take. Spent some time with my kids in the outdoors though. That makes me think the 6.8 is all right.

I have the option right now to buy either a Noveske 6.8 upper, a Noveske 300ACC Blackout upper, or a Noveske 5.56 Mod 0 chambered upper. After serious consideration of all of these posts many of them reactionary in nature as I made the bold attempt to state what was obvious to me I will just do what I plan to do! Which is have an upper that shoots inexpensive military surplus ammunition that can be purchased in large quantities for little money, have an upper that was designed for the cartridge that I intend to use, have an upper and barrel that does not require a special separate bolt and magazine, have an upper with a cartridge I already reload for, have an upper that will shoot a 62 grain or 70 grain TSX through anything I will point it at. I will avoid buying an upper that uses a Special Purpose Cartridge that has never really gained much ground in popularity and for very good reasons. There is only so much you can do with cartridges this size and the 6.8SPC is just not that much more. Finally I will not shoot pigs with varmint bullets, thanks for that tip.

we are back to how many angels are dancing on the head of my favorite cartridge.

There's knowing and there's guessing. You've shown yourself to be strong on the latter.

Leave the knowing to those of us that actually kill shyt with the 6.8 AND .223 on a regular basis.

How did the 556/223 get to be such a deer slayer all of a sudden? Here in Kayansizzz you ain't supposed to use something that small. Ostensibly, there is some real-world backing for the reasoning of the F&G. Of course, I don't want to go too far down that road. I mean, seein's how it is so hard for them to just locate a stinking mountain lion. I know a lot of folks here like the 223 for Whitetails, but I don't see the point. Unless that's all you have or all you have in a certain platform you want to use, I don't really get it.

At the risk of touting guesswork, the 6.8 and its ballistics look really sweet for Whitetails as long as the distance ain't too much.

I am choosing the most logical cartridge. No one said the .223 was the most powerful only that the power range between the two does not justify to me the added expense and difference of the 6.8SPC. How much powder can you cram into the small cases anyway? Buy what you want I will shoot what I want in the end what you do with your 6.8SPC will be no different than what I do with a .223. I have owned a bolt .222 Remington and 8 .223's in my lifetime of shooting it at paper and animals. I admit I probably do not have your vast experience with the cartridges. An intellectual decision based on experience and the factors I have already listed is my decision, its probably many other peoples decision.

My friends neighbors wife shoots doe's out of her garden with a .22 Hornet, any center fire .22 is legal in GA.

Jimmy,
I don't see that any of this is worth getting worked up over. I say shoot what you like. Sometimes a chambering choice is based on little more than you don't already have a rifle so chambered. That's justification enough for me.

You asked me what the 6.8 does better than the .223 and I told you what I think based on owning and shooting both. You're free to accept or discard what I've said, but I spoke honestly and without any antagonism, so I hope you will return the favor even if you disagree with me. But, understand that what I've told you is not based on what I've read; it's based on my first hand experience. I've enjoyed our conversations on scopes and I would like to continue with that level of civility.

You can do a lot of the same things with .223 as you can with 6.8. But to say the .223 will do everything just as well as the 6.8 is just not true, as it depends totally on what you're doing. For larger animals, the 6.8 will be more immediately lethal. Bullets that create larger wound channels kill faster. Heavier bullets that stay together will penetrate better. The 6.8 is not just a nominal step up in power level from .223; it's a pretty significant difference. 6.8 shoots 100 gr bullets at the same velocity that .223 shoots 75 gr bullets. Besides using significantly heavier bullets, the 6.8 case has 15% greater volume than .223 (36 vs. 31 gr water). With a high BC bullet, the .223 starts to narrow the gap at longer range, but the 6.8 is a moderate range cartridge, and does its job well within those limitations.

Whether the difference in cost to get that is worth it to you is always up to the individual. However, the cost difference to build one vs. the other is greatly overstated. I didn't buy a complete upper or lower; I built my AR entirely from parts I selected. The honest to goodness difference in cost to build my 6.8 vs. a .223 using the same brand components... comparing apples to apples... was a whopping $25 more for the 6.8! I bought the bolt head from Stag Arms. Their 6.8 head costs $60.00 vs. $45.00 for the .223. Their .223 magazines cost $20.00 vs. $30.00 for 6.8 magazines. I bought my barrel from White Oak Armory. There was no difference in the cost of the barrel for either, depending on which barrel profile you want. All other parts are the same, whether you go with .223 or 6.8. If you plan to buy a complete upper, Rock River's and Stag's 6.8 uppers are no more expensive than their .223 uppers. I've seen the same hold true with other uppers as well. At best, there isn't a huge difference in price, though that undoubtedly varies depending on whose upper you buy and how you have it spec'ed out.

Yes, ammo is more expensive for 6.8 than .223, as you can get cheap mil surp brass for the latter, but the price difference wasn't that big a deal for me. Cost to load 6.8 is not that much more expensive than .223 after you have a good supply of brass. In factory ammo, 6.8 is really not that expensive, maybe $5/ box more than equivalent .223. Shooting the 6.8 is quite a bit less expensive than shooting my 6PPC, all of my big 7's and .30's, and most everything I have except rimfires and .223's. But the fact is, to say a 6.8 cost way more to build is a fallacy, and although it does cost a bit more to shoot, not by a huge margin, comparing bullets of the same pedigree.

I freely admit I haven't stoked the .223 with 62 TSX or any "heavy" bullet and gone after big game with it. The reason I haven't is because I have too many other rifles that are way better suited to big game to press the .223 into that role, so there has never been a need. My .223's are used for zapping prairie dogs, and in that role, they are sublime. If .22 centerfires were all a shooter could ever need for big game then why would anyone shoot anything with more horsepower and pay more in ammo cost and recoil?

Ordered a couple more C-Products 6.8spc magazines two nights ago. Man those things are expensive at $11.99. laughing...

Sounds like we have the same barrel from WOA if you went 18", Rifledude. And yeah, there is zero difference in cost for uppers and rifles between 5.56 and 6.8spc with the major manufacturers.

One thing to keep in mind on this:



In order to seat those higher BC (heavier weight) .223 bullets for an AR, you start eating into case capacity because you're OAL is limited to the magazine.

There is simply no .223 bullet appropriate for Deer or hogs that will match the ballistics of the 6.8spc 100-110 TSX or Accubonds. The .223 bullets have a lower BC and considerably less powder capacity.

To top off the cost portion of the entire thing SSA is going to be producing a plinking round very soon that will have the retail price point of $12-$14 per box.

I see the 5.56 remaining the NATO standard, but think the AR/M 16s days are numbered.

I don't think the .223 will do anything the 6.8 will do, but I also don't think the 6.8 will do anything the 5.56 will do. They're two different cartridges. In a Varmint configuration, the AR 5.56/223 is capable of whacking p-dogs out to long ranges with little recoil. I don't think the 6.8 will do that. Also, while the 6.8 is a good deer cartridge, (if the range isn't too great) so is the .223 (if the deer isn't too large.)

Were I going to buy an AR type rifle, which I won't since I've had one since 1972, I'd without hesitation get a .223. If you only have one, that's the rifle to get. If you already have a /223, maybe a 6.8 for reasons still unclear to me.

Yep, I have the same 18" middie barrel.

And, you're right about using heavier .223 bullets in ARs. You have to seat them deeper to function in the magazines.