I sourced a 350 gr. bullet mold with the gas check base and thought it would allow the versatility of using smokeless powder. Or perhaps even use them with black powder, though the gas check is rather unnecessary in that instance. I already had the Lee push through sizing die, so no added expense there. I contacted a major powder company for suitable smokeless load data and the reply was basically: Obsolete cartridge, no SAMMI specifications, weak action, catastrophic failure waiting to happen. On the other hand when I contacted another major powder manufacturer they provided me with usable data for four bullet weights and two powders and psi data. I would publish my received replies but neither manufacturer would allow reproducing them without permission. So it's sort of disheartening to receive scary warnings about an "accident waiting to happen" when there are many documented smokeless loads shared by owners of the reproduction 1876. I have many pounds of "Old Eynsford" black powder available to load up my rifle. The thing is, instead of purchasing empty brass I purchased loaded rounds so they would be fire formed upon the first firing. Well those rounds are loaded with guess what, smokeless powder. Considering the many safe smokeless loads available for the Springfield Trapdoor what's going on here? There are thousands of repro 1876's manufactured and we can't have viable data? Even the Lyman 49th Handbook has a decent section for the 1876. It would be nice if it were expanded some. Okay, end of rant.