Need some help on these rimfire rifle bolts. Several photos.

I'm hoping someone may be able to shed some light on these. I can't find a match to what these bolts are for. The rim diameter of the cartridge these would hold looks to be about .430. Each bolt has a proof mark on it. The proofmark is PT which I believe is a French marking. The firing pin looks very familiar, but I cannot place. It reminds me of H&R, Mossberg type, but I found no match for it. Does anyone happen to recognize these bolts? I appreciate any info.