So I got my alien airsoft today. I charged the battery for 4 hours per the instructions. The problem is the magazine doesn't seem to feed bullets. On the page on Evike it said the high capacity magazine was supposed to hold like 160 rounds, but I can only get 21 in there. I primed up the wheel on the magazine all the way, but when I fire it will fire one good shot, and then I hear the spring in the magazine complete discharge it's energy end then it won't feed any more bullets. They don't even rise to the top of the magazine. So I have to wind the magazine again to even fire one more shot. Any advice here? I'm new to airsoft, so is there something I am missing here?