I recently bought an ARES M4 RAS-L and it was misfiring and finally jammed during a game. I took the gun apart, went into the gearbox, removed the tip of a screw (I've no idea how that got there) that had clogged my gears, and reassembled it. The issue now is that now I can't get my gearbox to fit into my lower receiver. I've tried hammering it and everything, and now I can get it to fit somewhat but my firemode/safety is getting stuck all the time. Sometimes when I put it in, I can't move the switch, other times I can, but either way the trigger is either stuck in safe, or it can be pulled even when in safe. Also, I got the spring slot banged up pretty badly, any tips on getting that up in shape?
Additionally, when the gearbox was opened I checked my piston and saw that the first 4-5 teeth had half of the tooth completely used up. My gun only fired about 600 or so shots, so I was wondering if the wear is excessive, and whether I should get a full metal piston.
