Ok, now I'm having a similar problem. I'm leaking from the bolt but I can fire no problem. I just replaced a torn AB o-ring with one that's 14x1mm. I've taken the back half off, oiled the crap outta it and still the same.
When I degass it, the bolt moves a bit forward but is still in the open position. I've tried resetting the bolt but I don't get anything different happening.
Of course, my tank's just under 1000 psi, but that shouldn't make that much of a difference, would it?