Why is my clip not feeding properly into my airsoft gun?

I just recently bought an upper level airsoft gun.It's my first upperlevel AEG that uses a wind-up/gear mag(where you wind up the gear at the bottom).My gun will only shoot 1 BB for every15 shot,unless i keep constantly winding.And when I take out my clip,(I'm guesstimating here) 7 BBs will fall out.Any reason why this is happening?Is there any way I can fix it or is my clip defective?