Is it common for a gun well into smokeless powder era to have BP proofs only?
I know that many Brit sports did not trust nitro powders at first and that up to WWI cartridges which were bought in bulk for big shoots were almost invariably BP, so high was the chance that some of the shots didn't or couldn't (older guns) shoot smokeless. But for a gun, with an essentially mass-produced action, not to have nitro proofs?
Did it have to be specified by the customer in the order, 'gun to shoot black powder only' or some such?