What upper for M855

[joeranger]

I bought a ton of surplus greentips thinking the zombies would have started rising by now. (and they would be wearing body armor

My AR really doesn't like surplus ammo. She is kind of funny that way.I have a 24in custom varmint and she has expensive tastes.

Kidding aside, I am heading to a gun show this weekend and would like to pick up a used upper for targets.
This is a military rd, but what civilian length/twist rate is best suited for this ammo?

 

[Skadoosh]

A twist of 1:10 or faster is good for M855

 

[Mike38]

My opinion, a 16 inch 1:9 does real well with those 62 grain green tips.

 

[kraigwy]

If you are going to get a new barrel (upper) anyway, why not get a 1:7. Besides the M855, you can shoot any bullet, like (55) to heavy (80).

Army does well with the M855 and 1:7s.

I found my guns pretty much match the army's test. My Colt SP1 with 1:12 shoots wash tube groups with heavy bullets, but I can keep them in 2 inches with M193 55 grain bullets.

My WOA 1:7 Uppers shoots anything from 52 grn match bullets to 80 & 90 grn Match bullets. Like the SP1 I can keep all the M193s in two inches at 100 yards.

Why limit yourselt to one weight bullet?