I'm not impressed with the crosman bolts either. They have it on all their guns that have a sliding bolt. I'm sure a metal receiver would help but probably not much. Did you try the piece of rubber wedged into the bolt trick? It helps a little.
Quote from: 2K1TJ on July 30, 2016, 11:41:42 AMDoes the bolt on a 66 have an o-ring? May try adding one if it doesnt.Yes, I put an o-ring on there from the 1377. I just barely grooved the drill bit to get the diameter right.I think it works pretty good the way it was blowing back. The trigger blew back too stronger then you can hold. The rubber spacer is worth doing. It's just a piece of fuel line. It makes the action better. Takes the play out too. I'm not sure if the pellet depth is right though. I think it gets pushed into the barrel. Is that ok? By the way, last reading at 12 pumps was 748 fps. It had some air not dumped though.
Does the bolt on a 66 have an o-ring? May try adding one if it doesnt.
Used my 760 PF as a test subject with a probe from a "78" 760.The brass bolt is replaced with a better solution. The stock brass bolt was very loose.