hehe a guy i know bought this lil clear mp5, and its 17 bucks from wal-mart, and surprisingly the rate of fire is fast 4 a AA powered gun, and its fun to shoot, but its only like 115 FPS
Well, it looks like it got hacked, but basically what I expect was going on there was the batteries got replaced with a 9V. Increases ROF. You can also add some spacers behind the spring for a bit more power.