Black powder loads different, shoots different, and cleans different than smokeless. Substitutes like Pyrodex are chemically altered, but load, shoot, and clean just like black powder. Your best bet is to get one of the great books on black powder cartridge loading like The Gun Digest Black Powder Loading Manual by Dr. Sam Fadala. Consider this book a must for your library. Suffice it to say, smokeless powder is loaded by grains of weight.
Black powder is loaded by grains of volume.
There are seemingly endless smokeless powder loads for every cartridge. With black powder or Pyrodex, there is one correct load. Black powder or Pyrodex is poured into the case to a level when the bullet is fully seated, the powder is slightly compressed about one eighth inch. Do not use a smokeless powder measure. Rather, use one of the brass black powder flasks or volumetric measuring devices commonly available to measure the correct amounts of black powder.