Common Firearm Terms

  • Action – The action is the part of a firearm that loads, fires, and ejects the cartridge.

  • AFTE – AFTE stands for the Association of Firearms and Tool Mark Examiners.

  • Ammunition – Ammunition is the cartridges that include a primed case, propellant, and projectile.

  • Barrel – The barrel is the metal tube that a projectile moves through after firing.

  • Base – The base is the part of the cartridge case that houses the primer.

  • Ballistics – Ballistics is the study of a moving projectile after it leaves the barrel of a firearm.

  • Black powder – Black powder is an older type of gunpowder that contained nitrate, charcoal, and sulfur.

  • Bolt – The bolt is the supporting mechanism on some firearms that has a firing pin, extractor, and possibly an ejector.

  • Bore – The bore is the inside of the barrel.

  • Brass – Brass is a slang term that refers to fired cartridge cases.

  • Breech – The breech is the end of the barrel that attaches to the action.

  • Breech face – The breech face sits around the firing pin.

  • Buckshot – Buckshot is the pellets typically loaded in shotshells.

  • Bullet – Bullets are the projectiles that eject from firearms.

  • Bullet wipe – The bullet wipe is the area around a bullet hole that happens due to bullet lubricant, lead, smoke, and debris.

  • Butt – The butt is the part of the firearm that you hold or place against the shoulder.

  • Caliber – The caliber is the diameter of the bore, typically expressed in hundredths of an inch.

  • Cannelure – The cannelure is the groove around the circumference of a bullet, used for crimping, lubricating, and identification.

  • Cartridge – A cartridge is a unit of ammunition that includes the cartridge case, primer, powder, and bullet.

  • Cartridge case – The cartridge case is the container for all of the components that make up a cartridge.

  • Centerfire – The centerfire is the center of the case head of the cartridge.

  • Chamber – The chamber is the part of the action that holds the cartridges.

  • Choke – The choke is the inside constriction of the shotgun bore, situated at the muzzle and designed to control the pattern of fired shots.

  • Class characteristics – Class characteristics are the features of a specimen that indicate the restricted group source.

  • Clip – A clip is a separate cartridge container used to quickly reload a firearm magazine.

  • Cock – To cock a firearm is to place the firing mechanism under spring tension to fire it.

  • Comparison microscope – A comparison microscope features two microscopes that are connected to an optical bridge, enabling the user to view to objects at the same time with the same magnification.

  • Cylinder – The cylinder is the part of a revolver that holds the ammunition.

  • Discharge – Discharging a firearm is firing it.

  • Double-action – A double-action trigger cocks the hammer and fires it.

  • Ejector – The ejector of a firearm ejects the cartridge.

  • Extractor – The extractor of a firearm withdraws a cartridge from the chamber.

  • Firearm – A firearm includes the action and barrel, used to discharge a projectile.

  • Firearms identification – Firearms identification is a discipline of forensic science that determines if ammunition was fired from a specific firearm.

  • Firing pin – The firing pin strikes the primer of a cartridge to initiate ignition.

  • Firing pin impression – The firing pin strikes the cartridge case, causing an indentation.

  • Forensic science – Forensic science is the scientific examination of physical evidence, used in courtrooms.

  • Gauge – Gauge describes the diameter of a shotgun barrel.

  • Griess test – The Griess test is a test to detect nitrites, which are residues that collect around bullet holes.

  • Grip – The handle of a shotgun is the grip.

  • Gunpowder – Gunpowder is the powder used in ammunition as the propellant charge.

  • Gunpowder residue – The unburned gunpowder is left behind as a residue.

  • Gunshot residue – All of the residues from firing a firearm collect as residue.

  • Hammer – The hammer strikes the firing pin to detonate the gunpowder.

  • Hammer block – The hammer block keeps the firing pin and hammer separated as a safety mechanism.

  • Headstamp – The headstamp consists of numbers, letters, and symbols and is stamped on the head of a cartridge case to identify where it was made.

  • Individual characteristics – Individual characteristics are marks produced by using tools, which distinguish tools from other tools.

  • Ignition – Ignition involves lighting gunpowder.

  • Lands and grooves – Lands are the raised areas between grooves inside the barrel.

  • Magazine – The magazine stores cartridges for a repeating firearm.

  • Magnum – The magnum is a type of cartridge with more powder, which increases the energy of the fired bullets.

  • Muzzle – The muzzle is the end of the barrel where the bullet exits.

  • Pellet – Pellets are small, round projectiles.

  • Pistol – A pistol is another name for a handgun.

  • Powder – Powder is the propellant in a cartridge.

  • Primer – The primer is the explosive material that ignites when struck.

  • Projectile – The projectile is the item that is propelled by the firearm.

  • Pyrodex – Pyrodex is a brand name of a type of black powder.

  • Recoil – The recoil is the backward movement that happens after firing a firearm.

  • Reload – Reloading a firearm involves reassembling the components.

  • Receiver – A receiver is a type of firearm that includes the firing and breech mechanism.

  • Revolver – A revolver is a handgun with a cylinder that has holes to hold the cartridges.

  • Rifle – A rifle is a firearm that is fired from the shoulder.

  • Rifling – Rifling describes the spiral grooves inside a gun barrel that make the bullets spin.

  • Rimfire – Rimfire describes the primer distribution around the periphery of the base of the cartridge.

  • Round – The military refers to cartridges as rounds.

  • Safety – The safety on a firearm prevents firing.

  • Shotgun – A shotgun is a long gun fired from the shoulder.

  • Shotshell – A shotshell is a cartridge designed to be fired from a shotgun.

  • Sights – Sights on top of a barrel help with aiming.

  • Silencer – A silencer can fit onto the muzzle of a firearm to muffle the sound it makes when firing.

  • Single-action – A single-action hammer has to be manually cocked every time before pulling the trigger.

  • Slug – A slug is a single projectile in a shotshell.

  • Smokeless powder – Smokeless powder is the modern gunpowder that smokes less than black powder.

  • Sodium Rhodizonate test – This test detects particulate lead or lead vapor around a bullet hole.

  • Stock – The stock is the frame that holds the barrel and action.

  • Striation – Striation is the parallel contours caused by force and motion.

  • Submachine gun – A submachine gun is a short-barreled automatic firearm.

  • Tool – A tool is any object used for a mechanical advantage.

  • Toolmark (impressed) – An impressed toolmark is the impression left behind after placing a tool against a hard object.

  • Toolmark (striated) – A striated toolmark is the mark left behind after moving a tool against and across a softer object.

  • Trajectory – Trajectory describes the curved path of a projectile between muzzle and target.

  • Trigger – The trigger is the firearm mechanism that the user moves to discharge the firearm.

  • Wad – The wad is assembled and placed into the head end of the shotshell.

This list provided by A Glossary For Firearms: All Terms and Gun Lingo Explained (snipercountry.com)