Centerfire versus rimfire ammunition: which statement is true?

• A. Centerfire has a primer in the center of the cartridge base; rimfire primer around the rim; centerfire is used for most handguns.
• B. Rimfire has a primer in the center; centerfire primer around the rim.
• C. Centerfire is used for shotguns.
• D. Rimfire primers are more powerful than centerfire primers.

Answer: (A)

The main idea here is how the primer is positioned and how that affects ignition and typical firearm use. In centerfire ammunition, the primer sits in the center of the cartridge base and is struck by the firing pin to ignite the powder. In rimfire ammunition, the priming compound is formed around the rim of the base, so the firing pin crushes the rim to ignite the charge. This difference in primer location helps explain why centerfire is used for most handguns: it can handle higher pressures, provides reliable ignition, and is reloadable, which makes it the standard choice for the majority of handgun calibers. Rimfire is mostly used for smaller calibers (like the common .22 variants) and is not typically reloadable, which is why it isn’t used for most handguns.