I'm pretty sure the AS50 has more damage per bullet than the Barret.
no it's actually worse; it takes the M82 1 bullet to kill with a stomach shot, as it takes the AS50 2. the AS50 is actually worse in every way besides reload time, scope sway, recoil, and looks; but I always seem to get lucky shots with it, as if the bullets slightly homed in on targets
I feel like such a boss when I kill other snipers with it :D