Yes, the actual number that has been mentioned by ballistic folks on other sites has usually been deterioration begins about 200 yards. I mentioned fifty because many consider the home defense, anti personnel rounds used by Police departments as not good for their home defense with an AR. I am a proponent of the AR for home defense as opposed to a shotgun but that is a different thread.

At the distances contemplated for AR use in home defense or close quarter combat (which is the realm of unmagnified red dots and 1-4 power scopes many of us buy) the heavier, hollow point anti personnel rounds produced by Hornady, etc. will serve just fine and have the same advantages they offer in 1/7 bbls. Of course the 1/8 bbl. will also do fine with it, even at longer than the 200 yd. distances I had mentioned.

Very long military rounds, intended really as mid distance sniper rounds that can be used in ARs without going to larger calibers, may present problems due to their lengths and require as fast a twist as possible.

An interesting sidenote is that in the early years of military use of the AR, the tendency of the bullet to spin, end over end, was touted as a big advantage in close quarter combat and the twist rates were much higher (like 1/12) than in common use today.