Old Crow
Hunter
The ammo drop balance really needs to be looked at. Finding AP and HP ammo a bit more often is nice, but it's almost to the point of never finding normal rounds. I'd say even at higher stages it should be like 50/50 on what you get between normal and AP/HP.
Or hell, always throw in normal ammo with the AP and HP. Like, give normal a 100% chance to appear with special ammo.