I bought one today that does not always want to cock. Piston and sear seem ok and manspring must be ok as it cocks sometimes. I think cocking arm catch spring is a cock up (more in a minute). Also I assume the gun should have a mainspring guide (there is one in the gun).
Right--the cocking arm spring looks home made and has a couple of extra loopy bits on the side that touches the arm. The other end of it rests against what seems to be a black rubber ball. I cannot see this being correct and I think it was added later to tension the spring. I think the 2 sides of the spring are touching sometimes on cocking and the rubber ball needs to be compressed before the gun will cock. I dont want to rip out a factory fitted rubber ball so will wait until someone on me tells me the correct set up , which I assume is the same as the 28, before I destroy a rare factory special edition.
Thanks