The only type of powder that should be used in muzzleloaders is called: _____

Black powder is the only type of powder that should be used in muzzleloaders due to its appropriate combustion properties and compatibility with the design of these firearms.

Explanation:

The only type of powder that should be used in muzzleloaders is black powder. Black powder is the only type of powder that should be used in muzzleloaders due to its appropriate combustion properties and compatibility with the design of these firearms. Muzzleloaders are firearms that are loaded from the muzzle, and they require a specific type of gunpowder to function safely and effectively.

Modern substitutes like smokeless powder can cause serious damage to the firearm and pose a significant risk to the user. Black powder is the traditional and appropriate propellant for these types of guns, known for its distinct combustion properties, which align with the design and limitations of muzzleloading weapons. It's important to follow safety guidelines when handling and loading any type of firearm.