Which muzzleloader type uses a cap that creates a spark for ignition?

The inline percussion muzzleloader is designed to use a percussion cap for ignition, which creates a spark when struck by the hammer. This system greatly improved reliability and ease of use compared to earlier ignition methods.

In inline percussion rifles, the firing mechanism is typically located in a line with the barrel, which allows for a more streamlined design. When the trigger is pulled, the hammer falls and strikes the percussion cap, generating a flame that ignites the gunpowder in the barrel. This design eliminates the need for a frizzen and makes for quicker and more consistent firing than the flintlock or matchlock systems.

The flintlock uses a flint and steel mechanism, the matchlock relies on an open flame for ignition, and the wheel-lock uses a spinning wheel to create sparks. Each of these alternatives has its complexities and disadvantages compared to the more modern inline percussion system, which is why it is favored by many today. Understanding these mechanisms helps clarify why inline percussion is the correct answer for this question.