The .30WCF/.30-30 case of course has more internal capacity than the .32-40 case. I would find it extremely doubtful it was ever loaded originally as a Black Powder round, if so it would have held more than 30grs powder. Everything I have ever read regarding it was that it was in fact the first non-military round "Introduced" as a Smokeless Powder round using 30grs Smokeless. As I understand it the mod 1894 action was actually designed for it, but it was not in the original release, due to further development of the "Smokeless Powder Steel" for the bbls being necessary so it originated chambering the .38-55 & .32-40. This Black Powder thing is often seen, but is as best as I can determine simply incorrect & based entirely upon the common designation of .30-30 resembling that of earlier BP rounds. As already stated though, this was not the original designation of the cartridge, it being the .30WCF.
There is evidence that some users attempted re-loading it with BP, without good results & Winchester brought out the .32WS as a dual purpose round which could be used with factory smokeless loads for a power level similar to the .30WCF or it could be re-loaded with BP for a similar level to the older .32-40, holding a little more powder, but not enough to make a really significant difference. The slightly larger bore & slower rifling twist made this more viable than with the .30.
