12mm

This article lists firearm cartridges which have a bullet in the 12 millimetres (0.47 in) to 12.99 millimetres (0.511 in) caliber range.

Length refers to the cartridge case length.
OAL refers to the overall length of the cartridge.
Bullet refers to the diameter of the bullet.Some measurements are in millimetres, others are in calibers, which are measured in inches

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