Seven hundred years experience with powder made from potassium nitrate, sulphur and charcoal.
So you really wanna use some artificial powder with a few decades experience?
BTW pitting in a black powder caplock gun may also be from corrosive caps. Or the salt water many swear buy as a bore cleaner. Yeah, percussion caps used to be corrosive, from the chlorate used in the priming compound.
BP itself, I don't really know but am fairly sure, is not all that corrosive. Early rifles using smokeless often have badly corroded bores now. Those shot only with black, and the same type primers, are often OK. Seems to me one of the products of combustion, black powder, is potassium carbonate. Which is slippery. It is also called potash, and to some degree inhibits corrosion from primer chloride residue, and whatever nasty sulphur compounds are formed.
Yeah, I like black. But then, I do live in the US and have had more powder than I'll ever use delivered to my door.