Technical terms in shooting

• Accuracy: the ability of a weapon to discharge a series of shots within the lowest tolerances at a given distance and under optimum conditions.

 
• Air rifles: rifles that propel ammunition by the expansion of compressed gas. In contrast to firearms, the pressurised gas is not generated by exploding propellant but is compressed mechanically inside or outside the weapon. Weapons where the ammunition is propelled by a different gas as air are also counted as compressed air weapons. Different methods are used to provide the compressed gas.

 
• Ballistic coefficient: abbreviated as BC, non-dimensional (without unit of measurement) ratio that indicates the efficiency of an object’s (e.g. a bullet or diabolo) in overcoming resistance e.g. in the air or water. The higher the BC is, the more aerodynamic the pellet or bullet is. The less the BC, the higher the drag.

 
• Calibre: the calibre is a unit of measurement for projectile diameter. The inner diameter of the barrel of the weapon is also termed calibre (or gauge). Where a rifled barrel is concerned, we distinguish between inner calibre, the diameter between the lands (the raised parts on the inside of the barrel) and the outer calibre, the diameter between the grooves (the grooved parts on the inside of the barrel). The word “calibre” is often used to mean the type of ammunition or type of cartridge.

 
• Cartridge: consists of the components necessary for firing a projectile from a firearm (usually case, propellant, primer, bullet) assembled in one unit.

 
• Crimping: additional fixing of a seated bullet in the case neck, which can be recognised by the rim of the case mouth. Reloaders use this to increase shot start pressure of the bullet and improve uniform burn rate of the propellant.

 
• Energy: kinetic energy of a projectile. Is measured in joules.

 
• Field target: hunting simulation using air rifles for shooting (open class up to 7.5 joules, open class up to 16.3 joules). The targets are mainly life-size metal silhouettes of small animals like rabbits, crows, squirrels or rats, which can also be hunted in England and the USA with air rifles.

 
• Hollow point: projectile that has a notch or aperture at the tip.

 
• Muzzle velocity: is the term used for the speed of a bullet or other ammunition or projectile as it leaves the muzzle of the barrel of a weapon, so for instance the barrel of a gun or a canon. VO is commonly used as a symbol for initial velocity as in physics.

 
• Primer: used to ignite cartridges or powder charges in muzzle-loaders. It was invented in 1818 by Joseph Egg.

 
• Projectile: ammunition fired from a gun (from the Latin proicere = to throw something forwards)

 
• Recoil: the reaction that occurs when a mass is accelerated. The recoil direction is the opposite of the direction of acceleration.

 
• Semi-wadcutter: projectile with a punched edge.

 
• Trajectory: the curved path of a projectile. Is influenced by velocity, form, mass, atmospheric density and the force of gravity.

 
• Wadcutter: projectile with a flat head.