This is nice. I call that gun the pea shooter when you're going up against people with armor lol. I've used it effectively before, but it's just let me down too many times where I know the shorty or revolver won't.
Never, EVER use the 9mm on against an armored player. You're bound to lose.
EDIT: Infact in class today, we were learning about a guy who had body armor and machine guns with armor piercing bullets. The cops couldn't do anything because they were only equipped with 9mms, until they went to a gun store and got some rifles to take him on.
Skill, Coordination, and Experience will lead a team to victory.