My friend just bought this about a week ago and it stopped working after about 500 rounds. We've used different batterys and replaced the fuse, and nothing has worked. Were trying to seperate the recievers and see if we see any pinched wires or anything but are having trouble. How exactly does one get into it? This is how far we've taken it down. Every time we put a fuse in and try it, it blows the fuse, but doesn't shoot.