What mechanism does a percussion cap use to ignite the powder?

The percussion cap ignites the powder through a straightforward and reliable mechanism involving a hammer striking a cap that is positioned on a nipple. This process is fundamental to the operation of percussion firearms, which became popular in the 19th century as a significant advancement over earlier ignition systems.

When the hammer strikes the percussion cap, it crushes the cap, creating a small explosion caused by the fulminate of mercury or another explosive compound housed within the cap. This small explosion generates enough heat to ignite the main charge of gunpowder located in the firearm’s chamber. The development of the percussion cap system provided a more dependable and weather-resistant means of ignition compared to earlier flintlock mechanisms, which relied on a spark generated by flint striking steel.

Other methods of ignition mentioned, such as using a flint striking steel or generating electricity to create a spark, do not apply to percussion caps and represent different ignition systems altogether. Similarly, utilizing a burning wick is characteristic of matchlock firearms, which were replaced by more modern systems like the percussion cap, enhancing the reliability and speed of firing a weapon.