Everything, ball chopping, air hog cleaning problem.
i bought this gun about 4 years ago and i liked it for about the first two days of use. then the gun began to chop a ball here and there but overall it was still okey . After that it began to chop a ball every other shot. This gun has about the worst blow back in all the paintball guns i have ever tried it tends to blow the balls back up the feed neck into the hopper again which sometime results in the ball breaking in the hopper, when this happens it would cover all the other paint balls i had in paint witch caused me to waste like over a hundred balls a game. this gun is very annoying to use and tends to piss off whoever is using it. it is a very cheap gun however i would recomend that u spend your money on a better gun even if it costs a hundred dollars more.
U WILL HATE THIS GUN..... if u have enough money i strongly recomend that u spend the extra money on a tippman 98 custom or a BT of some sort this gun is really not worth the effort!!!!!