Look for tiny burrs around the openings in the receiver too. Polish the bolt with some 800/1200/1500 grit and then crocus cloth. Check and make sure the cartridge lifter is working freely. Beyond that, while looking at mine, I can't see anything else that would interfere. I kind of doubt the mainspring is weak. Even a weak spring would close the bolt if nothing extraneous is in the way I would think.
I would be cautious about polishing the chamber. Maybe a tuft of 0000 steel wool on a stick spun in a drill motor, or some Flitz (or toothpaste) on a tuft of cotton waste spun likewise? Certainly nothing more, and very little of that.
Have you chambered a round and ejected it unfired to see if there are any marks on it pointing to a defect in the chamber?
Last edited by gnoahhh; 05/05/10.
