your problem is probably that the trigger sear is worn out... i had this happen to mine after like 200 shots... god i regret paying 250$ for that POS 50$us shit!
try finding a tm firing assembly, a friend did this and it solved the problem... i think he bought it off trinity airsoft.
as for mine i fixed it by jamming a super tiny screw in the worn out part and filing it to size...
your're in luck i still have the pics i took
