TexasCHLforum.com

Ran across this article today. Interesting info that is in contrast to much of what I have heard about barrel twist rates in AR-15 rifles.

Captain's Journal: AR-15 Ammunition And Barrel Twist Rate
http://www.captainsjournal.com/2017/02/ ... wist-rate/


American Rifleman: Testing The Army’s M855A1 Standard Ball Cartridge
https://www.americanrifleman.org/articl ... cartridge/

Nothing new here. In fact, the other NATO countries use 1:9 barrels. I have 3 ARs in 5.56/.223. One has a Wylde chambered 18" stainless heavy profile DMR barrel with 1:8 button-rifled twist. One has a Wylde chambered 16" stainless medium profile barrel with 1:8 5R polygonal rifling. One has a 5.56 chambered 16" M4-profiled ER Shaw military contract barrel with a 1:9 twist.

I use the two 16" barrels to shoot 55 & 62 grain bullets. I use the 18" barrel to shoot 62 - 77 grain bullets. Both of the stainless barrel makers (Odin Works for the DMR and Ranier Arms Select for the carbine) say they guarantee a certain degree of accuracy: 1 MOA guaranteed with match ammo for the 18" Odin Works barrel, and sub-MOA guaranteed with match ammo for the 16" Rainier Arms barrel. In practical application, neither barrel shoots as guaranteed with all brands of match ammo, and even then only when I'm having a very good day........and most of the time, I don't shoot match ammo in the Ranier barrel. When I do, it does shoot sub-MOA. But the fact of the matter is that the ER Shaw contract barrel is capable of 2 MOA or better when I'm having a good day, shooting mil-spec 55 and 62 grain bullets. Sadly, "good days" are fewer and fewer these days with my eyesight. The commercial ammo that has produced the best results in both of my 1:8 barrels is Hornady .223 Superformance 75 grain match.

I use .223 winchester powermax bonded 64 grain HPs to deer hunt through my AR15. I usually shoot around 1 MOA with it through a 1:9 stainless bull barrel. Would another twist rate be more accurate? Possibly, but it shoots plenty well for deer out to 250.

It isn't the weight of the projectile it is the length, however there is generally a correlation between length and weight.

I would like to find a reasonably priced 1-14 twist for an AR build.