Caliber: (n) The diameter of the bore and the projectile traveling through it. Measured in millimeters, or in hundredths or thousands of an inch (i.e. 9mm is 9 millimeters in diameter ; “.45 caliber” is 0.45 inches in diameter.
Caliber: (n) The diameter of the bore and the projectile traveling through it. Measured in millimeters, or in hundredths or thousands of an inch (i.e. 9mm is 9 millimeters in diameter ; “.45 caliber” is 0.45 inches in diameter.