What happens to the primer in ammunition when struck by the firing pin?

When the firing pin strikes the primer in ammunition, it causes the primer compound to ignite. This ignition is a crucial step in the firing sequence of a cartridge. The primer contains a sensitive explosive mixture that, when impacted by the firing pin, generates a small flame and pressure. This flame ignites the propellant (gunpowder) within the cartridge, which then produces the gases needed to propel the bullet out of the barrel.

This process does not result in the primer burning out in a way that would make it useless; rather, it is a rapid transformation that enables the firing of the cartridge. The energy generated by the primer is significant enough to start the combustion of the main charge. Understanding this mechanism is essential for safe handling and operation of firearms, as it highlights the importance of the primer’s role in ammunition.