I can tell you this much, the two aperture plates in there that hold the piston latch rod DO have to be facing the correct way. I had a similar problem early on in the setting up of my 12ftlbs destroked piston build on the RWS54 I have. Honestly at the risk of putting pie on my own face I can tell you that I THOUGHT the problem was the profile of my custom machined piston latch rod notch. After a LOT of back and forth doing testing and tearing it down etc I put the original piston back in and had the same problem. Then I realized it was the orientation of those aperture plates that was causing the locked action problem. Once I got them switched the rifle fired properly again. The trigger is a very robust design albeit with not the best feel or adjustment as some other higher end spring piston triggers but it is rather good. I went ahead and put the original plastic trigger blade in the mill and did the two screw modifications to it which helped a LOT. I am working on some other options to make it even better now. Once I get the Target stock completed I am working on I will get down to the trigger. Good luck with yours my friend..
A&N Precision Machine
CNC machining and prototyping
Port St. Lucie, Florida
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