Glossary of Firearms Terminology; Gun Dictionary

Firearms Glossary

Glossary of Firearms Terminology
This is not intended as a definitive or all-inclusive glossary, just an informal guide for common firearms terminology, in alphabetical order. However, it's quite a comprehensive gloassary, researched from many different sources.
Wild Bill Hickock Framed Set

Action
Working mechanism of a firearm. There are various types. Bolt Action, Lever Action, Single Action, Double Action, etc.

Automatic
A machine gun. Any repeating firearm that automatically ejects, chambers and fires rounds repeatedly, usually at high speed, with a single, steady pull of the trigger. Also called Fully Automatic.

Backstrap
The back of a pistol's frame, the back of the grip.

Ball
A type of bullet or projectile. Usually used in older firearms such as a flintlock, musket-type weapons.

Barrel
The strong metal tube of a firearm through which the bullet passes.

Barrel-Cylinder Gap
The clearance between the sides of a bullet and the bore of the barrel as the bullet travels down it when fired. In the US, the industry-standard tolerance of the Barrel-Cylinder Gap is from 0.0001 to 0.012 inches. A gap any larger will cause problems with firing and accuracy.

Black Powder
Gunpowder. Explosive mixture consisting of charcoal, sulfur and saltpeter (nitrate). Invented by the Chinese in ancient times.

Blank or Blank Cartridge
A cartridge that has the explosive powder charge but no projectile.

Blowback (Blowback-Operated)
Utilization of the force of hot, expanding gases released from firing the firearm. In modern firearms, the strong force of the blowback is used to eject spent cartridges and a spring recoil replaces them with new ones in the chamber. Also called "gas operated."

Blued or Blueing
The treatment of metal on firearms that results in a black or bluish-black finish, usually done with chemicals.

Blunderbuss
Precursor to the shotgun. Usually a flintlock weapon, shorter than a rifle or a carbine, longer than a pistol, that is identifiable by a large, flared funnel-like barrel. Used for short-range close-in fighting, often used on ships as well as by mail and stagecoach drivers. Also called a naval or pirate blunderbuss. Used from late 1600s to mid 1800s.

Bolt
Metal bar or rod that slides and seats and/or removes a cartridge.

Bolt-Action
Firearm's action, using a manual sliding and/or rotating bolt to operate.

Bore
The inside of the barrel, or other part that needs to be hollowed out.

Breech
The rear of the barrel.

Breech Loader
A firearm that is loaded at the rear of the barrel.

Buckhorn Sight
An open-top sight with curved sides. Probably so-named because the shape resembles antlers on a buck.

Bullet
Technically, the projectile portion of a cartridge that is blown off by detonation of the powder charge, and flies through the air toward the target, leaving the shell or casing behind to be ejected. People often refer to the entire cartridge as a "bullet." On older black powder or percussion firearms, the bullet was just a shaped piece of lead.

Butt
The very rear end of a rifle stock or the bottom of a pistol grip. In the Old West, the butt of a rifle or pistol was used as a secondary weapon by lawmen to subdue troublemakers. Very handy for cracking skulls! Sometimes referred to as "pistol whipping."

Buttplate
On a rifle, a covering of metal, wood, plastic or other material fitted onto the very rear end of a rifle butt.

Caliber
Interior diameter of the barrel, or the bore. Also corresponds to the size of ammunition that will fit in it.

Carbine
A rifle or musket with a short barrel, usually a military version.

Cartridge
A modern "bullet" or metal casing, which is an entirely self-contained piece of ammunition, with projectile, powder charge and ignition primer, all in one unit. Nowadays, there are mainly only three kinds of cartridge: rimfire, centerfire and shotgun.

Centerfire
A cartridge that is detonated by striking a primer button centered in its base by the firing pin. If a cartridge has what appears to be a "button" in its base end, it's a centerfire cartridge.

Chamber
The rear of the barrel, or part of the gun where the ammunition is placed, in position, ready to fire.

Checkering
The crosshatched pattern or texture on a metal, wood or plastic surface of a firearm, usually used to improve grip, or for decoration. Especially used on hammers and slides and grips.

Choke
The shaping or an attachment at the muzzle of a shotgun that directs the spray or pattern of shot as it is fired out.

Clip
A container or feeding system, usually spring-loaded, that holds cartridges in place, so that it can be inserted into a firearm's magazine. Sometimes, the clip is called a "magazine" or a removable magazine.

Compensator
A variation of muzzle brake that diverts escaping high-pressure gases upwards at the muzzle, reducing the general upward kick caused by recoil to compensate f or it, and improve accuracy.

Crowning
The rounded or beveled end surfacing of the barrel opening, (muzzle) used to protect the opening an d edges.

Cylinder
On a revolver, the rotating "wheel" that holds the cartridges, and allows them to rotate into position with the barrel for firing.

Damascus Barrel
On old black powder firearms, a type of barrel made usually of separate bands of twisted iron. If you have a firearm with a Damascus barrel, it is not considered safe to shoot due to age, and the fact that such construction will not withstand the stresses and pressures created by today's ammunition.

Deringer, Derringer
Originally a brand of very small pocket pistol made for easy concealment. Today, the term Deringer or Derringer (2 R's) is used to refer to just about any brand of very small and concealable pocket pistol.

Double Action
A pistol or revolver that allows the hammer to be cocked and released by pulling the trigger.

Dry Fire, Dry Firing
Pulling the trigger and sending the firing pin and other parts into their full range of motion and impact without using ammunition. Usually considered a bad thing to do, placing undue stress on the parts.

Dumdum
A bullet that expands or fragments on impact, causing more damage. A modern form of a dumdum would be a hollowpoint bullet.

Elevation
On a firearm with adjustable sights, elevation is the vertical adjsutment, that moves your aim up and down. With muskets, this term can refer to the clearance between the bullet and the barrel, also called the "barrel-cylinder gap."

Extractor
Mechanism that removes empty ammunition casings from the chamber so they can be ejected clear of the firearm.

Firing Pin
A strong metal rod or pin that forcefully strikes the primer of a cartridge, firing the firearm.

Flash Suppressor
Attachment (or integral part of the muzzle) that covers the end of the muzzle, hiding the flash created by firing a firearm.

Flintlock
Old form of ignition for firearms in the days before fully self-contained cartridges. A locking mechanism with a metal part that strikes a flint, producing a spark, firing the weapon.

Frizzen
On a flintlock firearm, a curved metal plate, usually hinged, which is struck by the hammer, which contains a flint. When the flint strikes the frizzen, it creates a shower of sparks, while springing open to expose them to the powder in the pan to ignite it.

Fully Automatic or Full Automatic
A machine gun. Any repeating firearm that automatically chambers and fires rounds repeatedly with a single, steady pull of the trigger.

Gas-Operated
Utilization of the force of hot, expan ding gases released from firing the firearm. In modern firearms, the strong force of the blowback is used to eject spent cartridges and a spring recoil replaces them with new ones in the chamber. Also called "blowback-operated."

Gauge
The inside diameter or bore of a shotgun barrel. A shotgun's gauge is determined by a formula of how many balls of shot taken from a pound of metal will fit in a certain bore size.

Grain
Measurement unit of a powder charge. One pound is equivalent to 7,000 grains of powder. 437.5 grains is equivalent to one ounce.

Grip
The handle of a revolver or pistol. Sometimes fully integrated, or mounted in pieces. Can be wood, metal, plastic, etc.

Grooves
Spiraled channels cut into the inside of a firearm's barrel, that cause a bullet to spin upon firing, stabilizing its trajectory and improving accuracy.

Half-Cock
Partially cocking a firearm's hammer so that it does not fall and set off the firearm. If you slip and let the hammer fall while a round is chambered, you will discharge the firearm.

Hammer
Moving part that hinges up on rear (on hammer-equipped firearms), and snaps back into place with force, detonating the cartridge. Flint-tipped hammers are also used on flintlocks, to strike the frizzen to ignite powder.

Handloading (Hanloader)
Building or rebuilding your own ammunition. Usually done for reasons of economy or increased accuracy by serious shooters or hunters. A spent centerfire casing can be reloaded with powder, a new primer and bullet, using tools and equipment. Requires knowledge and experience to be performed safely. Also called "Reloading."

Hangfire
A malfunction in the primer of a cartridge that causes a delay in firing after the trigger is pulled. Obviously, if you have a long or ongoing hangfire or misfire, DO NOT look into the barrel to see what's going on. Some people have actually (stupidly?) died doing this!

Hollowpoint
Bullet with a hollow area in the nose, that causes it to expand on impact, increasing its destructive force. Sometimes called a dumdum.

Jam
Misfire, caused by a mechanical part malfunction, or by a cartridge being stuck midway in the magazine or chamber. Also, almost any other kind of mechanical blockage in the firearm.

Lands
Inside the barrel of a riflled firearm, the raised areas of the metal surface, that remain above the cut rifling grooves.

Magazine
Spring-loaded container that feeds cartridges into the firing chamber. Detachable or non-detachable. Sometimes called a "clip."

Magnum
A longer version of a cartridge of the same caliber. The increased length is to accommodate more powder for increased velocity, power and range.

Mainspring
On a flintlock musket or rifle, a strong spring that holds the hammer back in the cocked position until released by pulling the trigger.

Misfire
When a cartridge fails to discharge, or to discharge properly.

Musket
A smoothbore barrel (no rifling) firearm. Usually an old firearm with a flintlock firing system.

Musketoon
Short barrel, smoothbore, muzzle-loading carbine. A short-barrel version of a musket. Similar to a carbine.

Muzzle
The end of the barrel, the opening where the bullet exits.

Muzzle Brake
Attachment or shaping at the muzzle to dissipate or reduce gas pressure in order to reduce recoil.

Muzzle Energy
The force (measured in foot-pounds) of a bullet exiting the muzzle. Similar to recoil.

Muzzle Loader
Firearm that is loaded through the muzzle, with a solid breech. Old smoothbores are muzzle loaders.

Muzzle Report
The loud bang or boom sound made by discharging a firearm. Also called "report."

Pan
On a flintlock musket or rifl e, a small bowl-shaped pan that holds a small charge of powder. When ignited by the flint striking the frizzen, it flashes down a drilled hole in barrel, igniting the main charge in the barrel.

Parabellum
General name given to cartridges measuring 9 X 19mm. Also the popular nickname of a famous Germa n Luger semi-automatic pistol in that same caliber, made by Deutsche Munitions Fabrik (DWF) beginning in the early 1900's. Parabellum is a latin term (si vis pacem, para bellum) meaning: "If you wish for peace, prepare for war"

Parkerizing
A dull gray or greenish finish on a firearm to prevent rust, or a verb meaning to actually do so.

Patchbox
On a musket or flintlock rifle, a small compartment in the stock, usually with a door or lid, used for storing patches of greased or oiled cloth, which is rammed down the barrel, and used to wad or pack the lead ball or bullet against the powder, providing a seal for better compression upon firing.

Peep Sight
Rear sight with a small hole or aperture, which one peeps through to line up on the front sight and the target.

Percussion Cap
On older "Cap and Ball" percussion revolvers, a small brass or copper cap, that contains an explosive such as fulminate of mercury, which is placed over a cone or "percussion nipple." When this cap is struck by the hammer, it detonates and ignites the main powder charge through a small hole in the cone or nipple, firing the weapon.

Percussion Revolver
An older black powder revolver, in which the hammer strikes a percussion cap, igniting the main powder charge.

Pinfire
Old, obsolete cartridge with a small pin protruding from the side, near the base, that when struck by the firing pin, fires the cartridge. Some of the very old Deringer pistols used a pinfire system.

Plinking
Shooting at informal targets, such as old cans or bottles, or whatever else is around. Sloppy target shooting. Sometimes called taking "pot shots."

Primer
Small charge in a cartridge that ignites the powder when struck by the firing pin, discharging it.

Receiver
The part of a firearm that contains the moving parts, or the action. In modern firearms, the mechanical area that loads and ejects a cartridge.

Recoil
The energy created by the explosive release of discharging a firearm, that pushes it back against the person shooting it. It can range from a gentle bump to a smashing, bone-jarring experience, depending on the firearm. Remember what physicist Albert Einstein said? "For every action, there is an equal and opposite reaction."

Report
The loud bang, boom or crack sound made by discharging a firearm. Sometimes called a "muzzle report."

Revolver
A firearm with a rotating cylinder that holds cartridges, and aligns them for loading, unloading and firing.

Rifle
Long-Barreled firearm with a rifled groove cut into the bore of the barrel.

Rifling
The grooves cut into the bore of a barrel, to cause the bullet to rotate when fired, improving stability and accuracy in flight.

Rimfire
A cartridge that has its primer in the base, and is ignited by having the firing pin strik e the edge (rim) of the casing, crushing the rim to ignite it. Modern rimfire cartridges are mainly found only in small calibers, such as .22 caliber.

Round
Informal way of saying "cartridge" or a shot. Example; "I fired a couple of rounds at them."

Sabot or Sabot Bullet
In firearms, sabots are only known to be used in old black powder guns. A sabot is basically an adaptor that fits onto the back end of a bullet, to help trap in gases for more compression, enabling a smaller bullet to be used in a firearm with a larger bore or caliber.

Safety
A locking catch or mechanism that prevents the trigger from being pulled, or otherwise prevents the firearm from being discharged.

Sear
Pivoting part of the action of a firearm connecting the trigger to the hammer and holding it in place until released by the trigger.

Selective Fire
Feature of a firearm that allows firing either on full-automatic, or semi-automatic mode, usually with the use of a switch or lever.

Semi-Automatic
A firearm that automatically extracts and ejects spent cartridges upon firing, then re-chambers a new one to be fired, and can repeat this action, one trigger pull at a time, until the magazine or clip is empty. This action takes place very rapidly.

Shot
Small metal balls, grapeshot or buckshot, used in shotgun cartridges. Shot comes in different sizes.

Shotgun
Firearm with a smoothbore barrel, used to fire buckhot or shot. Modern shotguns use brass-based plastic cartridges filled with shot.

Single Action
Firearm that requires the hammer to be manually cocked before pulling the trigger. On a single-action semi-automatic, you only need to cock the hammer before firing it for the first round, until it's reloaded.

Sight
Blade or protusion (usually above the muzzle) and/or a protusion with a notch or other shape to aim with on the rear portion of the firearm, usually above the receiver. The shooter then looks down the firearm and lines both of them up with the target. There are many different types of sights, some adustable, some are not. Also see Elevation and Windage.

Silencer or Silenced
Device attached to the muzzle of a firearm to muffle or reduce the sound produced (also called the "report") from firing it. Illegal almost everywhere!

Slide
On firearms (usually semi-automatic pistols) the top part of the action (usually the entire top of the pistol) that ejects and loads the chamber by pulling it back, sliding it back along the frame.

Speedloader
Any device that enables simultaneous loading of more than one round at a time. There are many different types of speedloaders, ranging from cloth strips for old weapons to using an extra preloaded cylinder for a revolver. With the use of modern semi-automatics, speedloaders are unnecessary because all of the rounds are loaded at once in a clip. Having an extra loaded clip would be considered a speedloader.

Spitzer
A bullet with a pointed nose

Stock
The long part of a firearm (usually a rifle or musket) held by the shooter, or braced against the shooter's hip or shoulder, to stabilize during firing. Can be wood, polymer, metal etc.

Submachine Gun
Automatic firearm that uses pistol ammunition. Usually a smaller version of a full-size machine gun. Used for close-range firing.

Take Down
Button, lever or other device that allows for quick disassembly of a firearm for cleaning, oiling and maintenance, transportation etc. &nbs p;

Tang
Protusions on the frame or receiver that connect it to the stock or the grip.

Top Strap
Top part of the frame on a revolver.

Wadcutter
Nickname for a target shooting bullet, A bullet with a truncated, flattened nose, designed to put neat, round holes in a paper target.

Wildcat Cartridge
Non-sta ndard cartridge.

Windage
On a firearm with adjustable sights, windage is the horizontal adjustment, that moves your aim from side to side.

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