How much powder do you use when loading a 32 or 34 caliber percussion muzzel loader?

Pistol or rifle? The ROUGH rule of thumb- start with the bore diameter. For a pistol, charge is 50% of the diameter- so about 16 grains of fffG. For a rifle, 100-200% of the bore- so 32-64 grains of fffG. You should check with the maker if they are still in business, and see if they have an instruction manual available. NEVER use anything but black powder, or a black powder substitute, such as Pyrodex.