The LEE dies fit any standard press with a 7/8x14 thread. That means about 99% of the presses in use. You don't need the big, expensive press. I paid $35 for my set and they work okay.
SR-4759 has been regarded for many, many years as the ideal substitute for Black in the bikg, old Blackpowder cartridges. You use it in a 38%-of-Black ratio. The Mauser used 77 grains of Black, so you multiply that time point-three-eight and you get 29.26 grains when using the SR-4795.
Dominion loaded smokeless in the .43 Mauser for quite a few years. Their powder was PINK (I took a round apart when I was still in schhol: completely amazed me!). SR-4759 has gone into and out of production so many times since I started handloading that I can't keep track of them. It 'dies' and then there is such a clamour and they have to bring it back because there is NO other satusfactory substitute. It, or something very close, has been in production for more than a century!
Black powder is a BARREL of fun, but the sulphur EATS (and brittles) your expensive, hard-to-get brass. I think I would stay with smokeless.
Yes, you could use a main charge of Black with 3 or 4 grains of a very fast smokeless right next to the primer. That was standard procedure for many years. You will have to WAD your charge to keep the powders from mixing and then lightly COMPRESS your charge.
MIDWAY has a couple of moulds for it. Correct bore diameter is .433 but the rifling is very deep, so you need a .446" bullet. Correct weight was 386 grains. The original M.1871 cartridge used a RN bullet, but this was changed in 1884 when the '71/84 came into use and basically the same bullet, but with a little flat tip, was used after that.
It's really a fun cartridge to shoot.
The Kar. '71 was the official rifle of the Kaiserliche Schutztruppe in German East Africa during the Great War, also of some other German Colonial Armies. A few .43 Mausers actually saw action in 1945 with the Volkssturm!
