Black powder rifles are firearms that use black powder as a propellant. This type of gun dates back to the 15th century and was commonly used in hunting and warfare. Black powder is a mixture of saltpeter, charcoal, and sulfur, which creates a rapid expansion of gas when ignited, propelling a projectile down the barrel. These rifles typically have a smoothbore or rifled barrel, with rifled barrels providing better accuracy. Black powder rifles are often used in historical reenactments and hunting, and they require a different loading process compared to modern firearms, involving loose powder, a projectile, and a primer.