I play it a lot for the 360. The problem is that when you start you're getting ass kicked because you're new to the game, your reactions have been dulled by the onset of puberty AND every frickin kid has a bigger gun!!!
Get yourself onto the search and destroy games when you're ranked high enough. It's small maps and lots of kills so you'll rattle through the achievements for your guns in a few hours.
Then get back into the free for all and spank the kids with your big gun and trash talkin
.GIF)