Caliber is a critical aspect of ammunition, but it is something that is also often misunderstood or misrepresented. As it relates to firearms, caliber by definition—according to Merriam-Webster—is either A: the diameter of a bullet or other projectile, or B: the diameter of the bore of a gun usually expressed in hundredths or thousandths of an inch and typically written as a decimal, such as .35 caliber.

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