Home Forums Hunting & Shooting AR and Tactical Rifles 6.8SPC Vs 308Win ??????

My wife's son was mentioning the other day that he was wanting to build a 308 on an AR platform. So I got to looking at what would be required and it appears that the 6.8SPC would do nearly everything the 308 would and still us the AR15 platform. What is the best larger than a 5.56 that still utilizes the AR15 platform??

30 AR, or something similar, but I think it is a dead ctg.

that is an interesting comparison though, will have to wait and see what others say

I've got a few friends with the 6 WOA which is the 6.8 necked down. They all love it. I think an 85 TSX would be around 3000 fps.

But my buddy with the 6.8 started shooting pigs with his and seems to love it now. Not sure what changed his mind.

You're talking two entirely different animals here. The 308 is superior as a cartridge, to the 6.8 in every aspect. The problem when you come to AR's is that the 308 WCF isn't available in an AR-15. You need an AR-10 to utilize the longer cartridge or any in its family. So when you talk one vs. the other you're really not talking about a situation where it's in the same platform.

So it comes back to what you want it for. One would assume hunting. The 6.8 is always going to be inferior for any sort of big game. If you step up to the 308 then you have the elongated platform to deal with. I have both and always get knocked on this but...IMO the felt recoil is actually less with my DPMS AR-10 than it is with the 6.8 mm M-4 (AR-15) that I have. Both are similar configurations. The AR-10 is noticeably heavier and I'm sure that has a lot to do with it. So you've got a trade-off there.

IMO the 6.8 is good up to medium game. Lots of hogs are killed with it. Whitetails are fine. It would probably be okay for a smallish Black Bear. The 308 was always thought to be in the province of these same animals and marginal on anything else back in the day, but I'd sure feel more comfortable with it if Elk or regular Black Bear were on the menu. The 308 will be more of a distance cartridge too.

If your main issue is home defense, then if you're even looking beyond the 556 it probably means you don't trust it. I do and so can't offer much in the way of support for either of the other cartridges opposed to the 556. I think the 556 is the logical choice unless you're talking some sort of sniper type long-distance deal and then the 308 is your way to go.

I don't have the die-sale figures, but the 6.8 SPC has to be the second-most popular AR cartridge and availability weighs heavily on my thinking in that vein. You can't shoot what you don't got and the AR-15 platform is limited to the cartridges it can handle just like any other platform. There may be other rounds that shade the 6.8 at the expense of being hard to obtain.

You can push a Barnes 85gr TSX in the 6.8 SPC to over 2900fps in a 16" barrel without straining anything. I also load the 95gr TTSX to over 2800fps, again in a 16" barrel. You decide just how large an animal you could kill with those.

My 6.8 is a box stock M4 configuration from Rock River. The seven pound weight and collapsible stock is extremely handy in an enclosed blind regardless of the amount of clothing you need to wear.

If you choose a 6.8, get a mid-length gas system. The recoil pulse is smoother and the guns supposedly have less problems than a carbine length system.

so far I know this. The MP10 with a Diavari MC 3-9x36 in an LT-104, supplied magazine and 10 rounds weights 10 pounds. This gun with 18 inch barrel gives me the impression it may be accurate but I have not shot it enough to know for sure as hunting is priority these days. Its on paper and hits the bullseye so I am hunting with it using WW 150 grain PowerPoints. It is longer than my AR15 and 24 ounces or so heavier than the DDV7 no sights upper, Victory HT, LT-104 LMT lower with sophmod and 10 5.56 rounds. Overall owning both I prefer the handiness of the 5.56, having killed animals with both now my opinion is that performance wise on deer up to 150 or so pounds under 100 yards, no difference except more blood with a .308, there is no quicker death with one or the other each will kill fast if you put the bullet in the right place neither will kill if you shoot him wrong. A bigger hole however produces more blood trail and you need to be more careful of the bullets with the 5.56.

If you value going to Academy sports and picking up a box of cartridges and don't mind the pound and a half more get the 308, it has no recoil compared to a bolt gun and the one I have gives strong hints of accuracy, but I am not going to post anything until I wring it out completely. Of course the 5R melonite barrel that Smith provides with this gun is a POS and DAB or DMS bandit will be be along in a little while to tell you about the magical RRA guns.

The 6.8SPC I assume would be similar to the 5.56, all work fine. In my "opinion" (note I said opinion)I think your splitting hairs regards the 5.56 and 6.8 but the haters are going to jump on me now.

Ethan edward Yes I agree the 6.8 is a different animal to the 308WIN which is why I stated "nearly everything the 308 will do" Having several AR15's I am looking at the best cartridge above the 5.56. I trust the 5.56 which is why I own and hunt with several but would like to have a larger bore sometimes. I think I myself might like the advantage of just swapping the upper and clips for a large mouse trap vs purchasing a complete new firearm.

Sounds like the 6.8 will do just what I am looking for "Kill medium game such as deer, hog & coyotes out to the 200 to 300 yd line" with a little more authority.

The step son doesn't own an AR15 so he would probably be better off to just just in with both feet and go with an AR10.


Anybody got a 6.8SPC upper they need to unload?

Federal can't make that [bleep] fast enough. They are selling so much of it overseas its crazy. We burned through an 18-wheeler load of it this year in the sandbox. Federal sells a Gold-dot load that you can't even buy the bullet here 'cause they can't make 'em fast enough. It'll be around.

I love the 6.8

What about the 6.5 Grendal. It can actually beat the 308 on downrange as it doesn't loose its energy as fast as a 308 cartridge.

I would like to see the 6.5 Grendel load that beats a 308 with its best load.

Please share the comparative loads.

The 6.8 SPC is the best and perfect round for the AR-15 Platform

finally someone mentions the grendel. to me its what the 6.8 should have been instead. to me I think of the 6.8 is just a harder hitting 223, its simply going to just hit harder than the 223 but still have about the same effective range as the 223. effective range being 400 maybe 450 yards. The 6.5 grendel on the other hand is loaded with high bc bullets that shed their speed slowly. the grendel gives you both the knockdown power in close like the 6.8 has but it also does ALOT better at 6-800 yards. so in my mind why not have both knock down and substantially longer range.

the problem with the grendel right not is you just about flat out can't get parts for it. barrels must be ordered and bolts aren't that easy to find. some people have been waiting over a year for grendel barrels. I want one myself but its either pay obscene amounts to someone that happens to have a barrel or order and wait.

Apparently you are unaware of the Berger 140 grain in the 6.8 it is no slouch at 800 yards

Is there an apples to apples comparison with the 6.5 Grendel and the 308?

All I can find is a 26, 28 and 30" barrel on the Grendel as well as being single loaded. I'm a believer in BC but what velocity does it produce in a 20" barrel?

No, it ain't got the stones. Neck it down to 6mm and you can get enough speed to do something with. Same with 6.8spc. What Cummins said about the 6.8 being a harder hittin' 223 is about the best description of it I've heard. Same range

sorry I missed you wanted an AR-15 platform, when you mentioned .308 in your post, I thought you were considering a 308 as well (and I had not even been drinking yet!) Sure 6.8 if you want something different, I always wondered about the 110 grain bullet in that caliber!

I mentioned that my wife's son was wanting a 308 Win on a AR platform and I myself had pondered the idea of needing a 308Win on a AR platform. I also mentioned that I have numerous AR15 platforms and was wondering if it might be advantageous for myself to just select the 6.8SPC over the 308 Win.

I can tell you this with certainty the 6.8 is much more destructive than the 223. I know I have both and much prefer the 6.8

If Robert Silvers hasn't been banned from this site too, he will be posting about how the 300 AAC Blackout beats all of them.