Pierced Primer

[killer_chicken]

Normal pin protrusion looks like what you can see at "A" in this image. It should be between .040" and .050". Note that the protrusion is controlled by the striker flange contacting the rear of the bolt head at "B". It looks like your pin tip is so badly damaged it may end up short after the correct contour and surface finish is restored.

Ok, I've got the firing pin "mostly" cleaned up, I say mostly because there was a small pit that I wasn't sure it was necessary to sand down and I'm worried about taking off too much material. Everything is smooth, and free from sharp edges, so I think it should be fine?

I'm not sure sure how to ensure the striker flange is contacting the rear of the bolt head when I check for protrusion, short of disassembling the bolt, which, from what I've read, should be avoided if possible. If I turn the cocking piece counter clockwise (as viewed from the rear), it allows it to go forward a bit, and the firing pin sticks out of the bolt head. The amount it sticks out is similar to the photo you've linked. It did not change much from the before to after the sanding. But I'm not sure if that is a valid way to check.

[Parashooter]

With the cocking piece in the forward position (uncocked), unscrew the bolt head a turn or two and then screw it back in slowly. You should be able to feel when the back end of the bolt head contacts the striker flange and also observe the cocking piece moving away from the rear end of the bolt. If everything is in order, the cocking piece will move back between 1/64" and 1/16" and the firing pin will protrude .040" to .050" from the bolt face when the bolt head is aligned with the bolt rib. Use the small end of a common slide caliper to measure the protrusion.