The original proof marks are for black powder only (or pre-nitro). It was not compulsory to do nitro proof until some time after 1900. Lots of guns went through on black powder proof only around the turn of the century. I had a great Churchill pigeon gun with BP proofs.

Later on, some one had it reproofed for nitro. Perhaps in preparation to sell it as it was not out of proof by bore diameter.

Last edited by MattH; 12/01/25 09:22 PM.
----MattH
President, Ga. Vintagers