HUNTINGsmart! USA Knowledge Base
Module 05 - HANDGUNS 101
HANDGUN CALIBER
Like rifles, handguns are sized by their caliber, which is a measurement of bore diameter in either hundredths of an inch or in millimeters. The distance could be measured either in inches or in millimeters, from land-to-land or from groove-to-groove, depending on the specific cartridge.