Because most people spray the body with ar's in hope to get the kill that or they try to rush instead of changing their play style. You can't rush with ar's anymore in a straight up gun fight like you use to use them at their advantage now almost like a scout in playing laid back don't camp but pick your fights wisely. I was using necrocasm yesterday in skirmish and was out killing thorn and hawkmoon and even last word on some people. You can't shoot the body and hope to get the kill get your headshots and they drop like flies. This coming from an avid handcannon user.