Meister Glock 17 Weak Blowback
 

I have a Meister (TM clone) Glock 17 that has been great except a few months ago it got a lot of sand and dirt in it at a game. I took it home and cleaned everything I possibly could and re-oiled it but now it has really weak blowback that is not even strong enough to cycle the slide sometimes.

I feel like it has something to do with the hammer not being able to hit the valve on the mag hard enough anymore but I couldn't figure out how to disassemble the hammer unit. I did take it out and give it a good cleaning.

Any ideas?

I had something similar happen to my TM G17 that I had a gundoc had a look at. I think he mentioned that the piston wasn't on right or was lose. Mine would only cycle if you angled the gun down.