A centerfire cartridge has a centrally located primer held within a recess in the case head. Most centerfire brass cases used worldwide for sporting ammunition use Boxer primers. It is easy to remove and replace Boxer primers using standard reloading tools, facilitating reuse.
Some European- and Asian-manufactured military and sporting ammunition uses Berdan primers. Removing the spent primer from (decapping) these cases requires use of a special tool because the primer anvil (on which the primer compound is crushed) is an integral part of the case and the case therefore does not have a central hole through which a decapping tool can push the primer out from the inside, as is done with Boxer primers. In Berdan cases, the flash holes are located to the sides of the anvil. With the right tool and components, reloading Berdan-primed cases is perfectly feasible. However, Berdan primers are not readily available in the U.S.
Read more about this topic: Cartridge (firearms)