Yeah, I have the problem with the bolt not recocking after each shot, it acts like there is no gas pressure, I found out why on mine:
I have a KWA MAC-11 with a magnesium bolt, After a few hours of shooting the un jamed and i owned it up to find that a plastic part on the bolt (The plastic tube on the spring that slides on the silver tube, you gotta take out the three screws in the back internals of the gun to see it) had broken off. No big deal I thought, then my gun began to not recock, so I lubed it, it worked well, for a short time. So i put it to rest for a while, I thought it was because it was cold out (im playing in winter XD). So I went on here looking for a way to help, and after a couple hours, I stumbled across this site. Anyways, if you completely rip the gun apart, and examine the silver tube and the plastic peice around it (its removable), you can push the tip of the silver peice in, a valve opens up, which takes in gas from the magazine, and stores it in the plastic peice. My plastic peice, broke beyond a wide washer, therefor causing a major leak, which doesn't give enough pressure to push the Bolt back.
As of now My gun is in peices, the spring in the plastic peice is stretched beyond repair and the pin that holds it in place is missing, anyone have ANY idea where i can buy a new magnesium bolt, or the plastic peice w/ a spring and pin? plz help
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