Are they not all black powder based in terms of ignition? I've met gun qualified people before, even seen cartridge cases built from primer, powder, a shot and a brass casing. What it is, it's the mechanical applied physics to cause the falling hammer to ignite the primer, and the mechanism for causing rapid fire from a larger chamber holding more bullets. I actually own the milling tool, the drills. A forge is outside of my property ownership status, but I'm also aware that individual parts can be purchased.
sorry for the delay.... I got sidetracked...
Actually, there are two kinds of gunpowder.... the original, "black powder" was invented by the Chinese, I think. It is a mixture of charcoal, sulpher, and saltpeter. It is technically an explosive... if you put a pile of it down, and hit it with a hammer, it will go bang. Firearms that use black powder are usually called "muzzle-loaders" because you load them from the front (muzzle) of the gun.
The other, modern type of gunpowder is called "smokeless" powder. It is not explosive, it is flammable. When burned, it produces MUCH less smoke than black powder does. ... hence the name. This powder is put into brass cartridge cases for convenient carry and loading.
That's just a very brief, basic explanation of gunpowder.