Glossary of Airgun and Field Target Terms

If you have an airgun or Field Target term that you aren't sure of the meaning, please email it to us and we will define it for you and add it to this page. Please let us know if you see a definition that is ambiguous or inaccurate.

Terms

AAFTA - American Airgun Field Target Association, the governing body for field target in America.

Action - A group of moving parts used to cock, compress air (in some models), load, and fire an air gun.

Adjustable Objective - The adjustment on a riflescope that allows the parallax to be adjusted so that the target or quarry is in perfect focus. Typically this adjustment is on the front of the rifle scope and has distance marking on the adjustment bell.

Airgun - A gun which propels a projectile through its barrel by use of compressed air or carbon dioxide gas (C02). Gunpowder is not used in this type of gun.

Air Reservoir - The holding tube or bottle used for holding air under pressure for a precharged pneumatic airgun. Typically the reservoir resides in a tube under the barrel or in a removable bottle.

Breech - The rear end of the barrel where the pellet is loaded.

Bore - The inside of the barrel of a gun.

Caliber - The diameter of a projectile, the distance between the lands in a rifled barrel, or the bore diameter in a smooth bore barrel.

C02 airgun - A type of pneumatic air gun utilizing carbon dioxide gas (C02) or air that has been compressed and stored in a metal cylinder, or air that is compressed by an external air pump. This type of air gun allows the firing of multiple shots without recharging.

Click - One adjustment of the windage and elevation turrets on a rifle scope. The distance one click changes the point of impact depends on the minute of angle rating of the rifle scope. Example, a scope with a 1/4" click adjustment would change the point of impact approximately 1/4" at 100 yards.

Dieseling - The ignition and detonation of low flash point lubricants due to the high temperature generated during the rapid compression of air in a spring-piston air gun.

Eye Relief - The distance behind a rifle scope's eyepiece at which you can see a full sight picture.

Field of View - The width of a rifle scope's sight picture at 100 yards or 100 meters. A wider field of view makes it easier to spot game and track moving targets.

Hold Over/Under - Changing the point of aim either above or below of the target (without adjusting the sights) to adjust for the trajectory of the pellet.

Kentucky Windage - Changing the point of aim either left or right of the target (without adjusting the sights) to adjust for wind effects on the pellet.

Lane - A shooting position/station in a field target competition.

Magnification - The power rating of a rifle scope indicated by the symbol "X". A 24X rifle scope makes the target appear twenty four times closer than it actually is.

Minute of Angle (MOA) - This is an angular unit of measurement which is approximately 1.1" at 100 yards. This term is typically used in defining the click adjustments on a rifle scope.

Mounts & Rings - Devices used to attach a rifle scope to a rifle.

Muzzle - The front end of the barrel from which a projectile exits.

Parallax - A condition that occurs when the image of the target is not focused precisely on the reticle plane. Parallax is visible as an apparent movement between the reticle and the target when the shooter moves his head or, in extreme cases, an out-of-focus image. Many scopes have a special range focus to adjust for parallax (adjustable objective).

Pellet - A type of air gun projectile made from lead.

Pistol - A gun that has a short barrel and can be held, aimed, and fired with one hand.

Plinking - Informal, non competition shooting at a variety of fun targets.

Pneumatic Airgun - A type of air gun which utilizes the principle of stored compressed air or gas. Divided into two sub-categories: single stroke or multi-pump pneumatics and compressed C02/air pneumatics.

Point Of Impact (POI) - The place that the projectile (pellet) hits when the airgun is discharged.

Precharged Pneumatic (PCP) - an airgun that uses compressed air as the means of propulsion. Typically PCP guns are charged to 3000 psi from a SCUBA tank or hand pump.

Rangefinding - Using the adjustable objective on a rifle scope to determine the distance to a target or quarry. While looking at the target, the adjustable objective is turned until the target is in clear focus. The distance is then read from the adjustable objective.

Rifling - Spiral grooves and lands in the barrel bore that provide a stabilizing spin to a projectile so that it will be more accurate in flight.

Sights - Mechanical, optical, or electronic devices used to aim a gun.

Single Stroke Pneumatic Airgun - A type of pneumatic airgun which uses one stroke of a lever to compress and store enough air in a reservoir or chamber for one shot.

Spring-Piston Airgun - An air gun which uses a manual lever or other device to cock a spring-loaded piston which compresses air at the instant of firing. The compressed air that propels the projectile is not stored in a reservoir prior to firing. This class/division includes gas ram and opposing piston types of guns.

Target Turret - Finger adjustable turrets (windage and elevation adjustments) on a rifle scope. Typically they are marked with a numeric scale for quick adjustments.

Trajectory - The flight of the pellet after it leaves the barrel. The pellets flight is an arc. How much of an arc depends on the pellet weight and velocity.

Zero - The distance at which the airgun is sighted in at. Zero is a reference to the trajectory of the pellet. Example, if you sight in your gun at 40 yards, your Zero point is now 40 yards.

Zero Shift - A movement of the point of impact at the Zero point after the airgun has been sighted in.