Checked the Making BP link. It IS informative. It is NOT black powder as it can be purchased commercially. It is commonly called Brown or Green powder. It will work but is not nearly as efficient as commercial BP.
The biggest difference comes in the way that the powder mix is combined and corned. There is a detailed description of the process at the beginning of one (can't remember which) of the BP load manuals. The process of milling is done with a ball mill over a lengthy period. This is followed by another lengthy period of combination or incorporation lasting many hours and involving considerable pressure, See this link:
http://books.google.com/books?id=Ykc...result#PPA3,M1
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