Hey, about six months ago I bought a brand-new KWA MP7 from Toronto Airsoft. I've only fielded it once for about an hour since then (it's too cold up here in Canada), but recently, I noticed that the bbs started to curve up! I turned the hop-up down to the lowest setting, but they still curve. When I tune the hop-up up more, the bbs also curve up more. Does anyone have any idea what could be happening?