Do not load by someone else's black powder information. Black powder loading is dependent on each brand of case with different available powder space and what bullet you use. Start by determining how far into the case will the bullets be set. Next, fill a case with BP until it sets 1/16" above where the bullet base will sit. Now measure the volume of that load and use it for your reloading.
As for corrosion using BP or substitute, the difference is the residue left in the barrel. Black powder leaves a soot containing sulfur, of which both will cause aggressive corrosion if exposed to high humidity. BP substitutes contain only soot, which is very hydroscopic. Humidity can cause corrosion, but not as aggressive as BP residue. Soap and water is the most effective bore cleaner for either, but is somewhat difficult to use with revolvers. Having lots of inaccessible areas, water can collect where it cannot be properly dried. Do not use petroleum oils in the bore or chamber for protection of BP guns unless you wipe down all oils before shooting. Oil and BP/Substitutes do not mix, leaving a sticky substance that will bind up your revolver fast. I find that smokeless powder is a fine alternative for antique revolvers if low pressure loads are used. There are many loads offer lower pressures than a case full of BP or substitutes and much easier to clean and protect.
