Black Powder is classed as an Explosive. That's why a lot of gun stores don't carry it. Dealers that want to sell real Black Powder must have federal licenses to have explosives. Insurance companies jump all over this being in the building.

Pyrodex, T7, American Pioneer Powder and the rest are considered a Combustable Substitute as it was explained to me. They do not have to get all the federal permits, licenses or have the storage facilities.

A close friend of mine who owns a small sporting goods shop carried Black Powder for a while. He stopped when it was demanded that the Black Powder had to be stored in a powder magazine when ever the store was not open. This meant that every night at closing he had to take the black powder off the shelves and return it to the magazine or was in violation of law. (as he explained it to me). Yet he was allowed to sell what ever black powder he had purchased for the store prior to the new regulations legally. Once he ran out, we all went to Pyrodex....