2nd AR, Which Caliber?

I have a 5.56 but think I want a larger caliber for plinking and possibly game and maybe getting into long range shooting out to 500 at steel.

Should I just go .308 or consider other calibers? I think price of ammo should come into consideration as well as ballistics performance. Lower consideration might be a lower that can work with different cartidges depending on the upper but not a big deal.

Id look at a 6.5 Ammo is a little more but I like it.

if 6.5 then which cartridge and why?

Keep your 5.56 for shooting steel at 500Y. Load some 73gr ELDM and you can shoot at 800Y.

Grendel.

Grendel. (just get an upper that you swap out) The BC of the bullets in this cartridge allow it to stay supersonic out to 1200 yards (Hornady AMax). You can also get plinker rounds for about $.50 per round. The 73 gr. ELDM in a 5.56 may work but you may have to get a barrel with a faster twist rate.

P_102

if you can afford it, 6.5 creedmoor,

if you upgrade to a AR10 - get a light weight one like the DPMS gen2.
I have a regular AR10 in .308 16" barrel that simply shoots lights out but with scope is over 10lbs. Plus you really don't need a heavy bull barrel if its going too be used as a hunting rifle

308

I settled on 9mm, 5.56 and .300 AAC for my own uses.

I've owned them in .308 and 7.62x39 as well.

Good luck with your choice.

The only AR I had was a 5.56. I wanted more energy and the ability to keep that energy to 500 yards. I crunched numbers, and looked at the cost of several options. Due to the nature of energy delivery, the huge amount of brass that is widely available, and the huge amount of bullets that are widely available, I got back into the .308 business, after being out of it for 3 years. Fact of the matter is, the 5.56 and the .308 are military cartridges, therefore there is a plentiful supply of brass for both.

I have spotted for several 6.5 Grendels, and they have flown just fine to 800 yards, shooting very precise, but it is impossible for them to deliver the energy of the good ole .308. The 6.5 Grendel is a great little cartridge, but I wanted more punch on feral hogs.

Agreed 100%. If you don't intend to hunt with it the Grendel is a pretty flat shooter to 500 no problem. The 308 will do that and include the energy. 308 is AR10 and requires a complete new rifle. The Grendel requires only an upper swap of the 556 you already have. 2 pins out, 2 pins in and done (maybe a different mag too). Of course like was said earlier, you could shoot heavier bullets to 500 in 556/223 and give me that extra money.

Depending on what you are wanting to do. 308 if like Fireman you are wanting to engage hogs at 500 yards Grendel if just wanting to shoot 500 and still drop hogs out to 400 yards or so. (Grendel has more energy at 400 than a 243)

For plinking and steel, follow the other advice (if you have the barrel twist) and shoot heavier .223 loads.

The 6.5 Grendel, 6.8 SPC, and .300 BLK are your main choices if you just want to swap an upper. If you're not an amazing shot, I wouldn't recommend any of these past 200-250 yards for game, as the energy levels just aren't there.

If you're really going to hunt with it I would suggest stepping up to the AR10 platform and going with (in order of my preference only) .308, 7mm-08, 6.5 Creedmoor or even .243. The new Savage MSR 10 can be had in .308 or 6.5 and doesn't weight much more than an AR15. The DPMS Recon GII is another option, as FJG mentioned. Either of those would work well. If you don't mind extra weight, you can get a PSA AR10 for about $600-700 right now. There are other options too.

300BO or 6.5G

How much energy are you wanting on target?

of course, you can never go wrong with the increased energy of a 308 out of a AR-10. However, my humble opinion is that it is harder to shoot an AR-10 well, and they are considerably more of a PITA to tote around.

My suggestion is 6.5 Grendel. It's NOT a 308, but comes in a smaller package with lighter recoil. It's more fun to shoot, Hornady box ammo is pretty cheap, and it's got plenty of power for range fun out to 500 and hunting a little bit closer.

I am very much a fan of the 6.8 SPC especially in the AR15 category of choices. Vital shot out to 200-250 is lethal but much further you lose a lot of Ft pounds. I like it bc its light, deadly and ammo is plentiful. There is no doubt the AR10 platform is a step up especially for 200 plus yard shots. 308 with 178 gr AMAX is catastrophic on hogs.

Can easily take an AR10 in 308 out to 800 with good optics.

I failed to mention, another factor.

As far as equal bolt face goes, .260 Rem, 6.5 Creedmoor, 7mm-08, and .308, my favorite is the 7mm-08, no doubt about it. However, AR platforms in .308 Win were more common to find.

Can always get a 7mm-08 barrel and swap it out

I am tempted.

Why do you favor 7-08 over 260/6.5C?

Oh no you didn't

Yes he did!!!!!

Wait for it.......

Oh snap.

Ok now I'm really curious about the 7-08

Need to get some good speed with the 73 to get it to 800. My bolt 223 won't get to 800 with my 75 BTHP Match (G1 BC .395). Admittedly, the accuracy nodes on it are pushing that bullet pretty slow. He'll be able to get more speed with 5.56 loads and he'll lose some due to the gas tax, but if he can find a hot load for the 73 or 75 that shoots good out of his rifle than he can make it.

Chad said he was getting a 68 grainer out to 800 yards on another thread. The Hornady 68 has a nice BC as well for a bullet that would run in a 1:9 twist, so that might be worth exploring too.

I'm shooting 75 ELDM at past 800Y and it has better ballistics than my 308 175SMK loads. Granted I shoot those 75 ELDM from a 26" and at more than 3000FPS.
But the 75ELDM will be too long for an AR and it won't feed from the mag. The 73 ELDM will work for an AR. With an AR you'll get reduced speed for both 223 and 308. I haven't run numbers, but I would think in an AR, a 73 ELD will be as good as a 308 load for shooting at 500Y (what OP wants) or even at 800Y.

Grendel if u want to switch lowers but 308 if u want a hammer out to some distance

Here:

http://www.precisionriflehunters.com/blog/

You could look into .260 or 7mm-08. My AR-308 build happening now is a 7mm-08. You can resize .308 brass.

I see.... Ballistics are similar. A 7-08 will be better for hunting and will have a slightly better barrel life. But a .260/6.5C will have a little less recoil and would have a slight edge on PRS type matches. Nevertheless...The 7-08 is great caliber.

Recoil in PRS matches with rifles weighing well into the teens of lbs and having recoil taming devices like breaks or suppressors there will still be a difference in recoil but recoil will be very light.

The 7mm08 was a popular long range wildcat before Remington standardized it with SAAMI. It was beating the 308 and doing it with less recoil. Never understood why Remington never made factory ammo in heavier bullet weights than 154 and that was with a not so sleek bullet, or at least that I ever saw and I have been shooting that round since 1982. The first rifles Remington chambered for it were the 700 Varmint and the 788 with a 18.5 inch barrel or at least that is what was in their catalog when I bought my 788.

Why would you think the 6.5 has any advantage? If it's due to not dropping as much, that is irrelevant. Elevation is easily corrected. I compete with a 6.5 Creedmoor since I have so much brass, and bullets. But if I were starting from scratch, is be shooting a 7mm-08 A.I.

As Kevin mentioned, when you get up in the M24/M40 contour, 24" barrels, great brakes, 30 oz. scopes, recoil is not a concern, as long as a guy stays with a short action.

Yeah, that's great. But the OP clearly stated ranges out to 500 yards.

I'll probably go with .308 AR10. I was leaning that way to begin and I think that this thread has helped me solidify that. I'm not too worried about the weight, I really just want something that is easy to get ammo and relatively cheap to shoot.

Thanks

one more question about AR-10 platforms. I know that there are different styles and you have to watch compatibility but are uppers and lowers interchangeable between the different formats or do you need to match uppers and lowers?

Nevermind. I see that they are not.

Armalite is different from everyone else.

6x6.8spc

AR10 is the Armalite platform.
PA10 is the Palmetto State platform.
LR308 is the DPMS platform that used by everyone else.

No votes for the 458 socom???

I've flirted with that one for a while, but as I understand it the recoil can be a bit much. I'm not particularly recoil sensitive, but it seems to me there's no need to absorb a lot of recoil while shooting pigs at night.

I bet most people that own them used them initially and slowly stopped using them while using their other calibers more. It seems like a novelty type item to me.

Yeah, it wouldn't surprise me a bit to hear many stories of the old .458 SOCOM being put in the back of the safe in favor of something a little more "civilized."

When I started seriously considering a non-.223/5.56 upper for an AR15, I gave it plenty of thought. I went through this process:

- the .300 BO just had no appeal on account of its pistol-like power and trajectory
- the 6.8 SPC was a little more appealing, but that short fat bullet is just going to run out of steam pretty quick
- the 7.62x39, pretty much the same story...more appealing than the BO though
- the best choice seemed to be the Grendel...while it's no .264 Win Mag, it seems to be a well balanced cartridge for both close-up work and targets at distance (based strictly on numbers, since I don't even have mine yet)

I looked at what do I get for the effort and expense. Ft/lbs are great, to a minimal distance, brass cost is very high, bullet cost is very high. Then I looked at .308. Brass is abundant, energy delivery is substantial in close, to 500 yards (all I was concerned with), made perfect sense to run a .308

For shooting hogs mainly at night I do not think it makes much difference. Most shots are going to be well within 200 life that shoot a lot and throw it away when it needs trimming and they are not even annealing. Something about the lower pressure of the Grendel with a thick case neck compared to lots of other rounds. Bullets you can find pretty cheap if you shop around for both and powder for every 3 round of 308 shot you use enough to load 4 grendels and have powder left over toward the 5th.



Like Double Naught Spy wrote on here about why he uses the Grendel it just works, Doing necropsy on hogs you can see the difference between a 308 and yards for most and inside 100 a lot of the time. At those distances I doubt there is a hog that would complain it was shot with a 308 or a Grendel.

As to cost Grendel brass is a little more expensive and face it most of us will loose brass shot from an AR when shooting pigs at night. But you range ammo Grendel brass lasts a long time. Though many shots. Hornday brass life is 12 to 15 shots from an AR and Lapua is more like 20. If you are using a bushing die that neck just doesn't grow much I know guys that get those kind of brass Grendel kill but both do it well enough that you have the hog to do the necropsy on.

To each their own, I will take the Grendel in the lighter more modular ( manufactures on same page) Grendel and have fun over the 308 but we all have our choices and that makes the world a less boring place.

All I know is that the Grendel is perfect. Maybe the .308 is perfect, too, but I know the Grendel is.

Love my 308. I'm shooting 178 gr. Amax and it is a pleasure to shoot. Buy my ammo from Chad in bulk at a very reasonable cost.

Everything I shoot with it is DRT with virtually no felt recoil. Love the light weight of my 6.8 but you have to be much more accurate and take head shots on the big hogs to get a DRT consistently.