Okay so here's a brief outline of what's been happening to my gun: -got a new gearbox because old one broke -had feeding problems an thought the air nozzle wasn't coming back far enough, so I sanded it down just a hair(bad idea I know) -bbs start just rolling out the barrel with no for ce at all -I replaced the air nozzle and the same thing happens What is wrong? The only other possible culprit is the hop up. And looking closer min appears lopsided where the bb gets fed in. Is it supposed to be like that? One side of the hop up chamber is thinner than the other so it doesn't look quite right. Any ideas?