I've been reloading for a 16" ar15 for a month or so, after reloading for precision with a 26" 223 savage bolt action, and I've noticed some very different preferences on optimal charge weight. The long barrel seems to prefer max loads of slower powders, and the 16"shoots best at minimums, with faster powders. 21.2 gr of h335 behind a 55gr hornady shoot moa, and then grow to almost 3" without revealing another node. I don't expect one hole groups with this gun, but it seems that a faster powders might be the right ticket for carbine length rifles. Does anyone have loads specificallyfor their 16" barrels? Please only answer if you might throw away a gun that would only shoot moa, because you would never wish that on anyone. Figuratively , not literally.