I had a muzzle loader about 25 years ago and black powder was classified as an explosive then. When you bought it you had to fill out and sign a form with all kinds of questions on it.kragluver wrote:You are correct - BP substitutes are considered flammables, but not explosives - just like smokeless powder. BP was reclassified shortly after 9-11 which is why so many gun shops now don't bother carrying real BP - they would be required to have special storage facilities, etc.
You could only buy it at certain gun shops at that time. They had to have special storage for it then.
I think the alternate was called Pyrodex and it was classed as a propellant. It was smokeless and did not foul the bore of the barrel as bad.