If you have an original '73 with a pore that is pitted / rough and have tried b.p. and found the results less than satisactory, you may want to try Pyrodex.
I have an original '73 .44 W.C.F. made in 1882, that has a somewhat rough, pitted barrel. With black powder, it shoots great........for about 10-12 rounds, then the accuracy starts falling off quickly as fouling accumualtes in those recesses.
Pyrodex to the rescue! It worked great in that '73.....a full box of 50 rounds could be fired with good accuracy from start to finish.
I also tried 777 but, in that rifle, it produced throat leading whereas Pyrodex did not.
Knowing the issue of oxidation with Pyrodex if not cleaned after firing, I used a 50/50 mix of white vinegar & water to clean and never had an issue with rust. (Sometimes though, I just fired several rounds loaded with that new fangled stuff and then cleaned with good ole' Hoppes and that worked fine.)
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