O-ring on 760 bolt?

[jlp920]

 I just did an overhaul on my 2001 760, and added about 50 fps . As I sit here on my deck plinking, I'm looking at the bolt and thinking "that wants an O-ring" any thoughts on tightening up that area and maybe dragging a few more fps out of this gun?

[Dave180]

I put one on a plastic bolt once. I assume that one is plastic.   It was on the 66 though.    Did you do a leak test from end of barrel?  If you yank out the magnet and insert a cut off drill bit shank of the same diameter and make it longer, you will pick up more fps.  The pellet can be moved up all the way till it sits right in front of the barrel lip.  Here's a picture here:

https://www.gatewaytoairguns.org/GTA/index.php?topic=75518.60