Bullets are usually categorised by calibre (nominal diameter) and cartridge case length. E.g. 7.62 x 51. (Millimetres).
Or, in some cases, it may be an Imperial measure, e.g. .50 (meaning .5 of an inch - 12.7 mm).
Further classification can indicate ammunition type (ball, AP, incendiary etc), user/ manufacturer (NATO for example).
Calibre is an approximation of the diameter of the bullet/ bore of the rifle.
Note that it's a nominal value only, for example the 7.62 bullet is actually 7.82 mm in diameter.
Caliber
The correct size of the bullet that fits the rifle.
Generally refers to size of projectile.
Caliber
Caliber
caliber
Are you asking about caliber or the actual size of the rifle?
Caliber is the size designation for rifle and handgun bullets. Guage is the size designation for shotgun rounds.
Caliber
Caliber
A 22 caliber rifle is a firearm and a BB gun is an air gun (Not a firearm) Now if you are asking about a .22 caliber air gun then the difference is in the size of the projectile. A BB is a hard round .175 caliber ball. The .22 caliber is a larger size pellet.
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