@Sidney Smith, they will learn right after they load the Pyrodex into their flint lock rifle and it won't fire.
It is sad that real black powder is so difficult to obtain, and after Pyrodex and Tripple Seven have been marketed as excellent substitutes for real black powder (they are not). The substitutes are acceptable in percussion locks, sort of, and generally available at local gun stores when only one pound of powder is desired to experience the firing of a traditional muzzleloading firearm. Even then, it often takes magnum caps and flame throwing nipples.