Adjusting head space on a rifle with a rimmed cartridge and a detachable bolt head, such as with the Mosin Nagant and Lee Medfords and Lee-Enfields, is much easier than on the sold bolt Mauser 1889 and later Mauser rifles.
The previous generation of black powder rifles used rimmed cartridges so the technology was already in place
The previous generation of black powder rifles used rimmed cartridges so the technology was already in place