Its either the trigger sear or the piston sear, I broke my trigger sear clean in half (the one that lays parallel with the bolt)
If it is shooting when the bolt snaps forward its most likely the trigger sear. If you don't have much money to spend on this gun than you should just get rid of it. Its what you get for buying a clone.
There is an actual MP001 upgrade kit that you can buy that comes with an entire cylinder kit, reinforced sears and a barrel if you pay for it all. Its very high quality but its not the best design. It'll run you about 200 dollars shipped
Alphabet: "But one thing I know damn well is no matter how much people hate me or how bad a deal goes, they are going to get what they deserve if I have to strap a dildos to my feet and do the riverdance."