Greetings Forum,
I'm looking to build a short barrel AR for fun and shorter range hunting, I have an Armalite AR10 that I want to slap a new short barrel on and swap the furniture. Looking to hit elk and steel targets out to 300 yards at the furthest. I have a 7mm mag bolt gun so a short woods rifle is a fun concept.
Armalite has their 13.5" competition upper in 1:10" twist rate, while a 13.5" barrel has a 1:8" twist rate. Now I've been told by reviews on the Federal website that shorter barrels do better with lighter bullets, which also need a gentler twist to get stabilized. I've also read that over-twisting bullets on a .308 AR is not too detrimental for accuracy. All the charts I've seen show that a 1:8 twist rate is needed for bullets heavier than 200gr, while the short barrel AR's excel with bullets in the 150gr neighborhood.
So my questions are as follows, what's the reasoning for cutting such a fast twist into the barrel and should I even be concerned about it?
