Note: I found this glossary of terms to be very informative and helpful so I am re-posting it here for everyone to enjoy. Trades
Guns and Gunsmithing Terms: A
Action: An Action is the combination of mechanical parts which make up the system which loads a firearm, launches a projectile and removes the spent cartridge casing from the gun. This system includes all the components which function in the loading unloading and firing process of the firearm. Two basic actions exist to carry out several styles of actuation (listed directly below): single action, which requires the user to manually actuate the hammer or striking mechanism; and double action which uses mechanical processes and parts to automatically actuate the hammer or striking mechanism.
- Automatic Action: Automatic Actions will repeatedly deliver the loading, firing, and extraction/ejection in a continuous fashion until the trigger is released or the feeding system (magazine) is emptied. Typically the parts and mechanism housings that allow a firearm to be fired automatically require approval through the United States Treasury Department, and regulations are enforced through their BATFE (Bureau of Alcohol Tobacco and Firearms Enforcement) division. Automatic Actions are also referred to at times as Machine guns.
- Bolt Action: The bolt action is a mechanism that requires manual manipulation by the user at all stages of the loading, firing and unloading process in order for the firearm to function. The bolt action uses a movable bolt to pick up a round, seat it into the chamber and lock it into place, where it can then deliver the primer strike, and subsequently, with help from the operator, be moved back to the original open position to extract/eject and release the spent cartridge casing. Upon moving it forward again, it can receive a new loaded cartridge and repeat the process, given the appropriate input of the user. The bolt action is inherently more accurate, and generally requires less maintenance to run smoothly.
- Lever Action: The lever action is a mechanism which utilizes a lever attached to several other key components to initiate and complete the entire loading, firing and unloading, and then subsequent reloading with a single full manipulation of the lever. It is an older design, but the engineering behind it is strong enough that it still exists in a large fashion today.
- Pump Action: A pump action is an interconnected mechanism which allows the forearm of the firearm to be moved to the rear and again to the front to function through the entire cycle of the weapon. Each full pump of the forearm will retrieve a cartridge, load the chamber, cock the firearm’s hammer or striking mechanism and upon firing, remove the spent cartridge and begin the action again.
- Semi Automatic Action: A semi automatic firearm is one which is also called a self loading firearm, as the action of the firearm is kept in a continual state of readiness to fire until the ammunition is spent, or the firearm is unloaded. The trigger pull which fires the projectile causes the gun to go out of battery to start the removal of the spent cartridge, the retrieval of a new one and the subsequent loading of that cartridge in the chamber where another trigger pull will repeat the process. Each trigger pull will actuate this process once.
Ammunition: Ammunition is the basic catch all name for ready to fire projectiles. Generally speaking, this would contain a set of components constructed to allow for easy loading and containment of a powder charge and a projectile, and a means by which to release that projectile, like a primer. An example would be a rifle cartridge which is a housing of brass or other metal which houses a powder charge and a projectile, as well as a primer. The primer is struck igniting the powder, which explodes to push the projectile out of a barrel.
- Small Arms ammunition: Small arms ammunition is a loose term which many use to describe ammunition of less than1 inch in diameter. It generally denotes a round capable of being fired out of a barrel that can be controlled solely by the operator.
Guns and Gunsmithing Terms: B
Ballistics: Ballistics is the science of the cartridge, projectile performance and the characteristics of a firearm launched object. It encompasses the physics of the flight of the projectile, as well as the science of the chemical and mechanical processes which occur during the expulsion of a projectile from a barrel. It is a combination of art and science prior to a specification being agreed upon, at which point, the science of ballistics takes over as a repeatable result is now obtainable by the operator.
- Terminal Ballistics: Terminal ballistics is the specific focus on the performance of a projectile and the variables surrounding it as it moves through or into a specific target.
Barrel: A barrel is the piece of material and the part of a firearm which houses the chamber and bore. This piece will stabilize and direct the projectile immediately after it is fired. Rifling refers to the helical or spiral patterned lands and grooves inside of a barrel used to stabilize a single projectile. Smooth bore barrels refer to a barrel which is without rifling, because the projectiles does not need additional stabilization.
BB: A BB is a any projectile in the shape of a sphere which is generally noted as having a .177 diameter, and can be incorporated in a shotgun shell as part of a mass of projectiles, or singularly, as in an air rifle.
Benchrest: A benchrest is a platform used by a shooter to stabilize their position in order to enhance accuracy; it is used for a variety of shooting and maintenance as well as performance tasks, like sighting a scope into its zero, and cleaning a gun during shooting sessions. “Benchrest” as a verb is also used to describe a shooting competition for long range shooting which utilizes such a platform.
Big Bore: Big Bore is a term generally used to describe anything larger than a .38 in a handgun; .30 in a rifle. Certain organizations also make minor adjustments to this standard.
Birdshot: Birdshot is a generic term usually used to describe pellets in a shot shell that are massed together with each one being smaller than one tenth of an inch in diameter. It is used as a general hunting round for birds and waterfowl.
Bore: The internal area of a barrel is considered the bore, without inclusion of the chamber. The bore is the place a projectile moves through before it exists the firearm.
- Bore Diameter: The bore diameter is the tightest tolerance spanning the distance between opposite sides of the bore. In a rifled barrel, this dimension is measured from the highest point on each side to the other.
Buckshot: Spherical pieces of metal measuring between about 2 tenths of an inch and .36 of an inch, they are assembled together to provide a mass of projectiles in a single round, each of which has lethal potential.
Bullet: A shaped projectile, other than a sphere. Generally speaking a bullet is stabblized with helical rifling to set a specific path for it to fly.
- Armor Piercing Bullet: A projectile designed specifically to penetrate armor. The projectiles typically hold a super hard or engineerd shaped inner projectile, or are made of specific materials to facilitate penetration. In 1968 the Gun Control Act started to regulate the distribution and legality of the AP (Armor Piercing) rounds for everybody outside military and law enforcement.
- Full Metal Jacket Bullet: A lead projectile clad in a copper sheath to keep lead from contaminating or fouling the parts of the firearm it comes in contact with. FMJ is the common acronym, and round nose projectiles are usually called FMJ.
- Hollow Point Bullet: A projectile designed to deform on impact to create a larger wound channel. The idea is to penetrate into the body cavity, and then stay there or open a larger exit point upon full penetration. A divot or hole in the nose is designed and engineered to open up to a specific depth and retain a specific total mass to provide repeatable expansion.
- Wadcutter Bullet: A wadcutter is a flat faced projectile used for target shooting to make clean holes on targets, so the shot placement can be seen more easily. Typically they are cylindrical but have a taper or truncation to allow better functioning in a firearm, instead of having a completely flat face.
Butt: The end of the gun which does not include the bore. The Butt Stock is the rear piece of material used to control the firearm.
Guns and Gunsmithing Terms: C
Caliber: the size of a projectile determines its caliber. The diameter of the bullet is a representation of the caliber. For instance a .308 caliber has a diameter of .308
Carbine: A generic term in use to describe the shortened action or overall size of a weapon. The Carbine is used for firearms which must be carried for long distances, or by active users.
Cartridge: See Ammunition above. A cartridge is a complete loaded projectile, powder and casing with a primer.
- Centerfire Cartridge: A single piece of Ammunition which has a primer centered in the back of the casing in the case head.
- Magnuim Cartridge: A single piece of ammunition designed specifically to enhance the velocity and projectile characteristics. Specifically the limits of the projectile are enhanced through any of several methods, which can include increased powder content.
- Rimfire Cartridge: A single piece of ammunition which has the primer placed in the rim of the cartridge, rather than as a separate piece added to the case head. A good example of rimfire cartridges are .22 Long Rifle ammunition. The firing mechanism will pinch the rim rather than strike the primer, setting off the explosion nd then the projectile.
Chamber: The portion of the barrel which controls the position of the cartridge so it can be repeatedly fired without safety concerns and with repeatable accuracy and characteristics. The chamber forms a tight seal around the cartridge casing as the powder ignites to keep the case from expanding or exploding.
Choke: The choke is a portion near the bore exit fo a barrel, which constricts the shot from the discharged shotgun shell to keep it in a repeatable pattern out to a further distance. The choke ranges from cylinder tofull with cylinder being a less constrictive taper, and full being a more constrictive one. The more restrictive the taper, the longer the shot will remain in a compacted mass; the less restrictive, the more the mass will spread as it gains distance from the bore.
Clip: A piece of metal or other rigid material used to load several rounds of ammunition into a magazine or a firearm. A Magazine is NOT a clip. Another name for a clip would be a Stripper clip; an example of a clip would be the mechanism that loads an M1-Garand.
Cocking: Cocking means to move a hammer into a position to then be released and move towards the firing pin or striking mechanism.
Cylinder: The cylinder is the cylindrical piece of the firearm which holds the rounds of ammunition in a revolver type weapon. The cylinder performs several functions and aligns the cartridge up with the bore and the firing pin to be fired. Each portion of a revolution will line a new shot up between the firing mechanism and the barrel.
Guns and Gunsmithing Terms: D
Derringer: Generic term for a small gun carried in a pocket or purse, and used as a last ditch or concealed weapon.
Discharge: The process of the projectile being forced out of a cartridge casing after the ignition of powder by the primer.
Double Barrel: A firearm may contain two barrels in a single framework. An example would be an over/under shotgun or a side by side shotgun.
Guns and Gunsmithing Terms: E
Guns and Gunsmithing Terms: F
Firearm: A device which incorporates a mechanism to launch a projectile via a mechanical and chemical process involving ignition of an explosive charge. This is a generic term, and usually refers to anything that can fire a bullet or other projectile in some manner and generally be controlled by a person.
Firing Pin: A firing pin is the mechanical piece which is used to impact the primer and cause the controlled firing of a firearm. Several examples exist, and often the firing pin can be referred to as the firing mechanism (though the entire mechanism is more complicated than JUST the firing pin) or the striker. Essentially a firing pin is the piece in the mechanical process which makes contact with the primer to ignite powder.
Flash Suppressor: A device which attaches to the muzzle end of a barrel to held redistribute and redirect the hot gases and the explosion exiting the muzzle behind the projectile to keep the amount of visual signature to a minimum.
Guns and Gunsmithing Terms: G
Gauge: The gauge of a gun is a unit to describe a specific measurement of the bore size in diameter. The specific term refers to the highest weight of a lead ball which can be fired out of the specific diameter. Generally speaking it refers only to shotguns, with the exception being the .410 shotgun which is not a gauge measurement, but rather a specific diameter measurement.
Group or Grouping: A specific set of projectiles having been fired from the same point of aim. A grouping is the size of the specific number of shots as it measures from center of impact to center of impact at its widest points.
Guns and Gunsmithing Terms: H
Hair Trigger: A light trigger pull associated with a trigger fired weapon. This type of trigger is described as such because in comparison to standard triggers, it is deemed to be so light that a hair’s weight being applied to it could fire the weapon. Generally speaking a hair trigger is too generic a term to apply to a specific and quantifiable amount of force required to fire a weapon, but rather, is used as a descriptive to explain an exceedingly light amount of force, compared to standard.
Hammerless: A generic term to explain the firearm which does not have an exposed or manually actuated hammer.
Guns and Gunsmithing Terms: I
Guns and Gunsmithing Terms: J
Jacket: The cladding surrounding a lead projectile; the combination of a shaped lead projectile and a Jacket comprises a full metal jacket bullet.
Jam: A generalization referring to a malfunction involving live rounds of ammunition. The concept of a jam is used to describe all battery/out of battery malfunctions by some people.
Guns and Gunsmithing Terms: K
Guns and Gunsmithing Terms: L
Lands: The raised portions of the rifling in a barrel. The opposite (valleys) are described as Grooves.
Load: The act of placing rounds of ammunition in a position to be fired. Additionally the word Load can be used to describe a specific variant of ammunition e.g. “…the load consisted of a 325 grain bullet and 47 grains of powder.”
Guns and Gunsmithing Terms: M
Magazine: a mechanism for holding ammunition in a position to be able to be used easily from the firing mechanism of the firearm. It should not be confused with a Clip. Generally speaking, the magazine has functionality independent of the firearm, in that it is holding ammunition under spring pressure to assist in maintaining the correct posture for a bolt or other part to retrieve a round from the top of the magazine to facilitate the loading of the chamber.
Magnum: See Magnum Cartridge listed above. Additionally the word magnum is often used to loosely describe the firearm which shoots a magnum cartridge.
Misfeed: A misfeed is the condition which exists when a live round fails to be fully chambered. A failure to feed and a failure to chamber is also a common description. Most often the concept is regarding a repeating or semi automatic firearm, though it can be used to describe severe failures with manually operated firearms in some settings.
Misfire: A misfire is a condition which exists when a live round is still considered live, and the projectile has not been expelled, despite the operator believing the firearm to have completed the firing cycle. Specifically, a misfire or FTF (failure to Fire) can be brought on by a primer malfunction, a mechanical inadequacy by some part of the firearm, damaged or damp powder, or any number of other reasons. Typically, the round is considered live, dangerous and still able to be “set off” and in most cases, there has been some level of firing pin strike to the primer.
Muzzle: The end of the barrel, at the front end of the firearm. The place at where the projectile exits the firearm.
- Muzzle flash: The gases and still burning powder that are exiting the firearm create a visible signature which can be seen launching out after the projectile.
- Muzzle flip: The upward movement of the barrel end, after the exit of the projectile. See also, Recoillisted below.
- Muzzle Loader: A muzzle loader is also generically tagged as a Black Powder gun. It is a firearm which loads via the muzzle end instead of the breech end of the firearm, and where a cartridge is composed of components using the barrel as a holding container, rather than a piece of brass, as will a cartridge fired weapon.
Guns and Gunsmithing Terms: N
Nose: The forward area of a given part. Specifically, the nose of the bullet is the forward area of the bullet.
Guns and Gunsmithing Terms: O
Over and Under: a two barrel firearm; for instance an over and under shotgun. A barrel is placed above another barrel, with a single frame used to house the firing mechanism.
Guns and Gunsmithing Terms: P
Pattern: the measurement and style of the spread of projectiles from a shotgun shell/blast. The pattern is the amount of spread and the way the spread moves out at a certain distance from a specific firearm and configuration. As a general rule of thumb the measurement of the size of the spread of pellets at 40 yards determines the pattern.
Pistol: A pistol can be used to describe all hand held firearms. Specifically however: a pistol is a handgun that is not a revolver.
- Automatic Pistol: A self loading or semi-automatic handgun. Automatic pistols do exist, but often their brand and model names will denote that they are an automatic pistol, rather than the designation: Automatic Pistol.
- Double Action Pistol: A handgun which has the entire firing process controlled by the trigger pull. The only manual operations for the operator is the loading and the pulling of the trigger.
- Single Action Pistol: A handgun where a manual operation is involved: the operator must cock back the hammer to make the pistol fire after loading, and before pulling the trigger.
Plinking: The general term used to describe basic and unimportant shooting. Typically, plinking involves cheaper ammunition or no specific target e.g. “I went plinking on some cans, and tree stumps.”
Powder: The combustible material used to build pressure and project the bullet or shot out of the cartridge or shell.
- Black Powder: Charcoal, sulfur and potassium nitrate formed the basis for the first combustible powders used in firearms. Black powder is incredibly unstable and creates a lot of corrosion on metal, a huge explosion and a lot of smoke and fire.
- Smokeless powder: a non-corrosive modern propellant which doesn’t create much smoke when ignited.
Pressure: The building up of gases in a confined space e.g. a casing by the ignited propellant. This pressure will launch the projectile.
Primer: a piece inserted into the primer pocket which funnels a small ignition source into the powder compartment. The primer needs to be struck to ignite (though extreme heat can also “cook off” rounds)
Propellant: See Powder above. The propellant is the compound or source of material which builds pressure behind the projectile.
Guns and Gunsmithing Terms: Q
Guns and Gunsmithing Terms: R
Receiver: The hub of the firearm, the receiver generally connects the basic working parts of the firearm. It also generally houses the firing mechanism and the action’s components. The receiver can also be called a frame.
Recoil: The inadvertent rearward movement caused by momentum in the firearm caused by the exit of the projectile and the equalization of pressure within the firearm.
Recoil Pad: A section of material that cushions the rearward impact from the gun onto the shooter. Usually rubber is incorporated in the pad to absorb shock.
Reload: The placement of the physical cartridge into the chamber and locking it into place where it can be fired. Reload can also be used to describe a cartridge that has been used a second time (or thereafter) and is not fresh from factory.
Revolver: A handgun which has a set of revolving chambers set into a single cylinder to align with the barrel to shoot cartridges (or lead balls in the case of a black powder revolver).
Rifle: A long gun, fired in a position from the shoulder. The bore has rifling to stabilize a single projectile at a time.
Rifling: Rifling is the stabilization features built into the interior of the barrel. The peaks and valleys called Lands and grooves twist the bullet as it moves through the barrel. The flight path for the projectile, as a result of rifling is the same point of impact as the point of aim.
Guns and Gunsmithing Terms: S
Safety: A specific mechanism used to prevent accidental or even purposeful firing.
Shotgun: A long gun similar to a rifle, but which fires a shell comprised of a group of pellets or projectiles to create a larger impact zone, and deliver more projectile weight on target.
Shotshell: A single complete round of ammunition for usage in a shotgun. It contains a load of projectiles inside of a wad (a cup) with a powder charge and a primer to set it off.
Skeet: A shooting sport which utilizes shotguns to fire at flying discs, launched from a machine to simulate a bird flying away. Skeet shooting is a popular sport for shotgunners.
Sporting Clays: A shooting sport involving multiple trap machines as used in skeet shooting, as well as various terrain settings.
Stock: The portion of the firearm (usually, specifically long guns) that is not used in the firing process as an active part. The stock is usually made of wood or composite materials and only serve to enhance handling of the firearm in most cases.
Suppressor: A piece which serves as an attachment to the firearm specifically to dampen the sound for that firearm. Additionally, a suppressor could be used to hide the flash signature as well as the sound signature. Another name for a suppressor in many circles is: Silencer.
Guns and Gunsmithing Terms: T
Trajectory: The curvature of a projectile during its flight path.
Trap: A device to launch a clay target.
Trap Shooting: A shooting Sport where multiple targets are launched out at the same time to be shot down.
Trigger Lock: A safety device to keep the trigger from being depressed.
Trigger Pull: The trigger pull is the amount of force that a trigger requires to actuate its connected parts.
Guns and Gunsmithing Terms: U
Unload: To remove ammunition from a firearm.
Guns and Gunsmithing Terms: V
Velocity: The speed of the projectile; specifically, the rate at which a projectile moves in a single direction.
Guns and Gunsmithing Terms: W
Wad: A cup shaped part in the shotshell that holds the mass of projectiles in front of the powder charge.
Weapon: In the sense of a firearm; a weapon is a generic term used to describe a firearm which is used to defend or to make offensive maneuvers against a target or combatant. Some people do not refer to sporting guns as weapons, but rather firearms.