His clip had 21 bullets in it, he fired 11 to get that kill. Watch the bottom left corner which displays his ammo, plus, watch the players health, it shifts 5 times, meaning he hit the guy 5 times. At exactly 4 minutes, you can see the damage numbers clearly from mid range, 56 damage headshots, 45 damage body shots, I'd be willing to say there's nothing special about this gun, I'd defintely say the video is likely staged. I really don't think anything about this AR is overly special, I really believe the other players are just terrible. On a side note, if you have a fireteam of 5 mates and yourself, and join a match of rumble, does this mean you're pitched against your mates in the match?