Firearm Glossary

A comprehensive list of firearm-related terms used on this site.

Glossary Terms

Ammunition & Ballistics

  • Ballistics

    The study of projectiles in motion.


  • Black Powder

    An early type of gunpowder.


  • Bullet

    The projectile fired from a rifle or pistol.


  • Caliber

    The internal diameter of the firearm barrel, usually expressed in inches or millimeters.

    Example: .45 caliber, 9mm


  • Cartridge

    A complete unit of ammunition, consisting of a case, primer, powder, and projectile (bullet or shot).


  • Gauge

    The diameter of a shotgun barrel, related to the weight of a lead ball that fits the bore.

    Example: 12 gauge, 20 gauge


  • Primer

    A small explosive charge that ignites the propellant.


  • Shot

    Small, usually lead or steel, projectiles fired from a shotgun.


  • Smokeless Powder

    A modern type of propellant.


Basic Firearm Components & Anatomy

  • Barrel

    The metal tube through which the projectile travels.


  • Bore

    The interior of the barrel.


  • Breech

    The rear part of the barrel where the cartridge or shotshell is loaded.


  • Buttstock

    The part of the firearm held against the shoulder.


  • Chamber

    The part of the barrel that holds the cartridge or shotshell ready for firing.


  • Cylinder

    The rotating part of a revolver that holds multiple cartridges.


  • Frame

    The main structural component of the firearm.


  • Grips

    The part of the firearm held by the hand.


  • Hammer

    The part of the firing mechanism that strikes the firing pin or cartridge directly.


  • Magazine

    A container that holds cartridges or shotshells to be fed into the action.


  • Muzzle

    The front end of the barrel where the projectile exits.


  • Receiver

    The part of the firearm that houses the action.


Condition & Features

  • Antique Firearm

    Generally defined as a firearm manufactured before 1899.


  • Curio & Relic (C&R)

    A specific classification under US law for certain firearms of historical interest.


  • Factory Letter

    Documentation from the manufacturer detailing a firearm's original configuration.


  • NRA Rating (of Condition)

    A system for grading the condition of firearms.


  • Patina

    A surface discoloration caused by age and oxidation.


Firearm Types & Actions

  • Action

    The mechanism of a firearm that loads, fires, and ejects cartridges or shotshells.

    Example: Bolt-Action, Lever-Action, Pump-Action


  • Bolt-Action

    An action operated by a rotating bolt.


  • Breechloader

    A firearm loaded from the breech.


  • Carbine

    A short rifle.


  • Lever-Action

    An action operated by a lever.


  • Musket

    A smoothbore, muzzleloading long gun.


  • Muzzleloader

    A firearm loaded from the muzzle.


  • Pistol

    A handgun.


  • Pump-Action

    An action operated by a sliding forearm.


  • Repeating Firearm

    A firearm capable of firing multiple rounds without manual reloading after each shot.


  • Revolver

    A handgun with a rotating cylinder containing multiple chambers.


  • Rifle

    A long gun with a rifled barrel designed for accuracy.


  • Semi-Automatic

    A firearm that fires one shot per trigger pull and automatically loads the next round.


  • Shotgun

    A long gun designed to fire shot shells.


  • Single-Shot

    A firearm that holds only one round at a time.


Historical & Manufacturing Terms

  • Cartouche

    An ornamental frame or panel, sometimes containing markings on a firearm stock.


  • Gunsmith

    A person who makes or repairs firearms.


  • Militia

    A military force composed of citizen-soldiers.


  • Ordnance

    Military weapons and related materials.


  • Patent

    A government grant protecting an invention.


  • Proof Marks

    Marks applied to firearms to indicate they have been tested for strength.