Home Forums Hunting & Shooting AR and Tactical Rifles 308 twist for AR

Getting ready to order my barrel and I have a choice between 1x8.5 and 1x11. I want to shoot subs and supers and want the better twist for both.

There's not really a good twist for both. I would go with a 1-11" or 1-10" and see how the subs do with those twist. Of course, develop the sub loads without a suppressor to make sure they are stable. An 8.5 twist is really just too fast for standard velocity ammo with a .308.

Would have to lean to the 8.5, running 7 in my 300/221.

You may not get to top speeds with supers, that being said, I ran 6.5 twist in 223, and was easily able to hammer out 52s at max speeds, which I was told would never happen.

Worst case with 8.5s as noted, you'd have to run the supers a bit slower than normal.

I'd be careful about 8.5 stabilizing subs though...

I just order a 308 barrel for a AR 10 that I'm building I went with 1 in 11". The 8.5 is too shoot heavy bullets at subsonic speeds. BHA told they were having some issue with the 8.5 twist.

I hope this help

1 in 8" works for 220 Matchkings, subsonic in a .300 BO. I have some 240's and will experiment with them as well.

My AR-10's are both 1 in 10"

BHW told me the 8.5 was good to go a couple months ago and the one I bought appears to shoot very well. I haven't had time to work with it much but the 40 or so supers that I have run thru it appears to be shoot excellently.

I think 1-11 would be too slow for the subs.

KSMITH,

If you want a gun to primarily shoot subs, get a .300 BLK on a AR-15 receiver. The .308 AR platform isn't the best choice for shooting subs and supers due to the limits of magazine length, the difference in twist rates, and the fact that they rely on gas to cycle the bolt.

If you just want to shoot subs every once in a while but will primarily shoot supers through it, go with a 11" or 10" twist in the .308 AR platform.

Not necessarily.

My Sako TRG owners manual states specifically that the 11" twist will stabalize subsonic rounds. I have never done it myself, but I will take Sako's word for it.

length of a 194 Lehigh and its speed at 1000 fps, will not stabilize in an 11, the makers even claim 8 may not work... I know 7 does...

I'm curious as to what cartridge you're asking about. 300 BO, 7.62x51/308 Win, or something else?

.308 WIN