There's several black powder substitutes, but the original propellant works VERY well. Run hotter primers, use a home made copper drop tube, SPG lube, and a cardboard wad (waxed is best).

MV variations are less (sometimes in the single digits over a ten shot string!) when BP is used and your loading technique is uniform. Ask what the long range BPCR shooters have done as regards accuracy- it's pretty amazing!
Clean up is really easy, except for the added chore of washing the cases, less likelihood of leading, and it's what the firearm was designed around.

You are going to have to cast your own bullets for these rifles for best results regardless of powder used, so why not not go all the way, it's very little extra trouble once you've sorted out the few extra steps.

Don't worry about ruining your barrel by using BP, after all, the VAST majority of rounds that have been through it were just that, and it survived until now...
Information
Warning: This is a relatively older thread
This discussion is older than 360 days. Some information contained in it may no longer be current.