Centerfirepatroner

Centerfirepatroner are a category of firearm cartridges in which the primer is located at the center of the base of the case. This design contrasts with rimfire cartridges, where the primer compound is distributed around the rim. Centerfire cartridges are the dominant form of ammunition for rifles and handguns, and they are also common in many shotgun loads.

Construction and primer systems: In centerfire cartridges, a small metal cup containing the primer compound is seated in a recessed primer pocket. When struck by the firing pin, the primer detonates and ignites the main propellant charge. Centerfire primers are commonly of Boxer or Berdan design. Boxer primers use a single flash hole and have the anvil integrated into the primer, making reloading and priming the cases straightforward. Berdan primers use the case as the anvil and require multiple small flash holes in the base; Berdan cases are more difficult to reload.

Usage and advantages: Centerfire ammunition is capable of handling higher pressures than rimfire types, enabling a wide range of calibers for rifles, handguns, and many shotgun loads. The design also allows easy replacement or reloading of primers, which is favored by civilian reloaders and ammunition manufacturers. The vast majority of modern firearms chambered for centerfire cartridges rely on this system.

Safety and variations: The primer pocket can be crimped for military or duty ammunition to prevent primer setback. While Boxer-primed cases dominate civilian markets, Berdan-primed cases persist in some regions and applications, where reloading may be more challenging.

Comparison: Rimfire cartridges place the primer on the rim of the base and are generally limited to smaller calibers and lower-pressure loads. Centerfire cartridges cover a much broader range of sizes and uses and are the standard for contemporary firearms.