Canadian Firearms Safety Course (CFSC) Practice Exam

A rim-fire cartridge ignites through the mechanism where the firing pin crushes the priming compound located in the rim of the cartridge. In rim-fire ammunition, the primer is placed in the cartridge case rim itself rather than being a separate component. When the firing pin strikes the rim, it causes a deformation that compresses the priming material. This compression generates sufficient heat to ignite the priming compound, which then ignites the propellant powder inside the cartridge case, resulting in the firing of the bullet.

This design contrasts with centerfire cartridges, where the primer is located in a separate, centered cap at the rear of the cartridge. Rim-fire cartridges are typically used in smaller caliber firearms, making them distinct and specialized in their ignition mechanism. Understanding this relationship between the firing pin and the rim is crucial for recognizing how different types of ammunition operate and ensuring safe handling and operation in firearms.