.177 (4.5 mm) ... The standard airgun calibre for international target shooting: Note that .22 airgun is not used at all for competitions shot to ISSF standards. Pellet diameter is nominally 4.5 mm, with a range of sizes in .01 mm steps to allow exact matching to specific guns for best accuracy. This is not a calibre for home bullet making as the necessary precision is too great to be achieved relatively cheaply.
.22 ... A rimfire calibre, much used in target shooting and often synonymous with the term, Small-bore. It is used in International competitions over both 25 and 50 metres outdoors and 25 metres indoors. Within the UK it is shot over 25 yards indoors and 100 outdoors. It can be shot with reasonable accuracy out to 200 yards, but beyond this distance most sights do not have enough vertical adjustment to allow for longer range shooting. This is not a reloadable round. Normal diameter is .224 inch with a 40 grain unjacketed lead bullet.
.22 Long ... An old round, not much used today. It has the case of the .22 Long Rifle with a 29 grain bullet.
.22 Long Rifle ... The standard .22 rimfire cartridge for target rifle and pistol use. It can be loaded to supersonic muzzle velocities with light bullets, but for target shooting it is usually just subsonic with a 40 grain bullet.
.22 Short ... Only used these days as a target shooting round for timed fire pistol competitions. The case is shorter than the Long and it is fitted with a 29 grain bullet.
.223 (5.56 mm) ... The standard NATO small arms calibre, not used very much in the UK for long range outdoor target shooting. It is a centre fire cartridge and can be reloaded. Normal bullet diameter is .224 inch and weights range from 40 to 70 grain, with the heavier being favoured for long ranges.
.38/357 ... The most popular cartridge for reloading in the UK. The two dimensions are used to distinguish between the older, low powered .38 and the Smith & Wesson uploaded .357 Magnum, introduced in 1935. The .357 cartridge case is .135 inch longer than the .38 case so as to distinguish between the two. The nominal bullet diameter of both is .357 inch and the standard bullet weights are 148 or 158 grains.
7.62 (or, 762 or, .308) ... 7.62 mm, or .308 inch is the NATO standard machine gun cartridge calibre and much used in the UK for Full-bore rifle shooting outdoors at ranges up to 1200 yards. It is a centre fire cartridge and is often reloaded. Bullets are .308 inch diameter and range from about 110 to 200 grains, with those in the 150-160 grain bracket being the most common.
9 mm ... A centre fire calibre, much used by the military in both handguns and sub-machine guns. Not much used in the past as a target round as it is not easy to download and maintain functionality in semi-automatic guns. This is less of a problem today since the ban on such guns in the UK. Even so it does not have much of a following, due possibly to its relatively short range, even in carbines. The actual bullet diameter in Imperial units is .354 inch and normally the bullets although a bit on the light side at 115 grains can also be fired from .38/357 guns.
.41 Magnum ... A centre fire pistol calibre, not much used in the UK. It has a higher velocity than the .44 magnum with lighter recoil, it was introduced by Remington in 1964. Bullet diameter is .410 inch and typical weights are 180 or 200 grains.
.44 Magnum ... Introduced in 1956 by Remington, probably the most widely known high powered pistol cartridge, thanks to films such as "Dirty Harry". It is a centre fire cartridge, easily reloaded and accurate at quite long ranges (up to about 300 yards, especially in a carbine). Bullet diameter is .429 inch and an average weight is 240 grains.
.45 ACP ... Made famous by the gun that fired it, the M1911 Colt self-loading pistol (and also the 'Tommy Gun', or Thompson Sub-Machine Gun). It is a centre fire cartridge which itself is quite accurate at short ranges (up to 100 yards), but was originally intended for military use rather than target shooting. It is not a 'Magnum' round. Bullet diameter is normally .451 inch and average weight 230 grains.
ACP ... Automatic Colt Pistol.
Accidental discharge (AD) ... Sometimes called an, 'unintentional discharge'. Any firing of a gun which is not deliberate.
Action ... The mechanism of a gun by which it is loaded, locked, fired and unloaded.
Aim ... The process of aligning the gun with the target, usually by means of the sights.
Aiming Mark ... That part of the target which is used to align the sights onto the target. Usually, but not always the aiming mark is a black disk in the centre of the target sheet.
Aiming picture ... The appearance of both sights and target when they are correctly aligned. See also, sighting picture.
Airgun ... A loose term applied to any rifle or pistol that uses some form of compressed gas as the propellant. Air rifles generating over 12 ft/lb of muzzle energy and Air Pistols over 6 ft/lb are classed as firearms and must be held on a Firearms Certificate in the UK.
Ammunition ... The name given to the 'fuel' used by all types of gun. It must be realised that 'bullet', 'round', 'cartridge', 'nature', 'pellet' and 'projectile' are all parts of the make-up of ammunition. See the individual entries below for more information.
Anti-splash Curtains ... Curtains made of a rubber compound (in the UK the material is often called by its trade name of, Linatex) and hung in front of the Bullet Catcher (see below) so as to stop any back-splash from the bullets when they break up on impact.
Aperture Sights ... The standard type of sights used on air rifles and .22 rifles for target shooting. The sights consist of a rear unit with a small hole in it which is used to centralise the eye. A fore sight containing a ring, in the centre of which the (round) aiming mark is placed.
Are you ready? ... The question asked of competitors in timed fire events just before the timing commences.
Automatic ... A somewhat misleading term used to describe a semi-automatic pistol. A semi automatic is a self-loading gun which fires one shot for each pull of the trigger. A full automatic is a machine gun, i.e. a gun which continues to fire once the trigger is pulled.
Ball ... Either a standard cylindrical bullet (see below) or literally a round ball which is often used in Black powder guns, especially smoothbores.
Ballistic coefficient (BC) ... A measure of a given projectile's ability to overcome air resistance in flight when compared to a standard projectile used to calculate ballistic tables. The BC will always be less than 1 and the higher the number the better. For example a BC of .39 is better than one of .142, especially as the range increases.
Ballistics ... The study of what happens to a fired projectile. The study is divided into, internal, external and terminal ballistics. For target shooting purposes it is the first two which are important.
Barrel ... That part of a gun along which the bullet or pellet(s) travel when fired, it is usually but not always circular in cross-section.
Barrel length ... Normally this is the distance from the muzzle to the chamber and it includes the chamber itself. This measurement does not include accessories or barrel extensions like flash suppressers or muzzle brakes. The barrel length of a revolver is the distance from the muzzle to the breech end immediately in front of the cylinder, it does not include the cylinder itself.
BB ... 1) Round ball Airgun projectile of .175 inch diameter, much used in the USA for casual 'plinking' and seldom encountered in the UK. 2) A round shotgun cartridge projectile of .181 inch diameter.
BB Cap ... Bulleted Breech Cap, an almost obsolete .22 rimfire cartridge, usually powered by the primer alone and firing a very light bullet. It is physically much shorter than a .22 short rimfire round.
Bench Rest ... a) A form of shooting done with the gun supported in some way, either partly or wholly, on a 'bench' rather than solely by the marksman. b) A device for testing the accuracy of guns and ammunition: see Machine Rest below.
Berdan.. A centre-fire primer system developed by Hiram Berdan (an American) in 1858. It is characterised by having multiple flash holes and an integral anvil in the case. By one of those curiosities of fate, the Berdan system is used by the British armed forces and the Boxer system (by a Briton, Edward Boxer) by the Americans. Berdan cases are not as easy as Boxer cases to reload, due to the multiple, non central flash holes making removal of the fired primer more difficult: see below for Boxer
Bipod ... A twin legged support for a rifle, musket or carbine, usually fixed at the end of the stock away from the shooter and now illegal for competition use under ISSF rules.
Black-Powder (BP) ... Gunpowder used to operate muzzle loading guns. BP is classed in the UK as an explosive not a propellant and so an explosives licence , which is issued at no cost on application, is needed to both buy and store it. Although it is not normally called, 'smoky powder', it is notorious for the clouds of grey-white fog that it produces on being fired. This can be a real problem on indoor ranges unless equipped with adequate ventilation. See the entry for smokeless powder below. The basic ingredients are saltpetre (potassium nitrate), charcoal (carbon) and sulphur: see Gunpowder below.
Blank ... A cartridge loaded without a bullet. On firing it produces the usual loud 'bang' but with little danger to life. Note a) 'Blanks' are not to be considered as being 'safe' as close to the body the blast of hot gas and wads from the muzzle are distinctly dangerous. Note b) Some blanks do in fact have a bullet, usually made of either wood, or more usually these days, wax. This is so that automatic and semi-automatic weapons can function normally when shooting such ammunition. These blanks can kill, especially at close range.
Blow-back ... The method of operating low-powered semi-automatic guns. The bolt is literally 'blown' open by the cartridge when the gun is fired. It is normally used for .22 rimfire ammunition only, as any more powerful cartridge would require either an excessively heavy bolt and / or a very strong spring to keep the breech sealed until the pressure had dropped to a safe level before opening the chamber.
Bluing ... An oxidation (rusting) process normally applied to externally visible firearm metal parts. It is controlled by applying oil (usually heated) which mixes with the nitrates used in the process. The oil prevents further rusting by sealing the metal. This gives the metal a blue/black colour. It is also possible to "brown" guns by a similar process.
Boat tail... The tapered rear end of some bullets, used to increase ballistic efficiency at long range by reducing atmospheric drag. So-called because in plan view the bullet outline resembles that of a boat.
Bolt ... a) A steel rod-like assembly similar in design and operation to a normal door bolt, which moves back and forth in the action when operated by the shooter's hand. It seals the cartridge in the chamber during firing and extracts it afterwards. b) In automatic and semi-automatic repeating guns, it loads the rounds from the magazine and unloads the fired cases, it may only have a passing resemblance to a door bolt and may not turn to lock.
Bolt Action ... A type of gun, usually, but not always a rifle, which is loaded and unloaded by means of a bolt. It can be either a single shot, or a multi shot gun.
Bore ... a) The interior diameter of the barrel of a firearm between the chamber and the muzzle. b) The British word for the calibre of a shotgun (in America they use 'Gauge'). A 12 bore shotgun has an internal barrel diameter of .729 inch and this is derived from the diameter of a lead ball of such size as 12 of them would weigh one pound.
Bore diameter ... In rifled arms, the diameter formed by the top of the lands, in smooth bores, the diameter of the barrel just ahead of the chamber.
Bore line ... An imaginary line projected from the muzzle of a gun along the centre of the bore.
Boxer ... A centre-fire primer system developed by Edward Boxer (a Briton) in 1858. It is characterised by having one central flash hole and the anvil as an integral part of the primer. Very easy to reload and used by the American armed forces and most home reloaders in the UK. See above for Berdan.
Breech ... The end part of the barrel nearest the shooter with the chamber into which the cartridge or projectile is loaded.
Breech loader ... A firearm loaded through the breech end. Note that this does not automatically imply a gun firing metallic cartridge cases: see muzzle loader below.
Brisance ... In addition to strength, explosives display a second characteristic, which is their shattering effect or brisance (from the French meaning to "break"), which is distinguished from their total work capacity. This characteristic is of practical importance in determining the effectiveness of an explosion in fragmenting shells, bomb casings, grenades, and the like. The rapidity with which an explosive reaches its peak pressure is a measure of its brisance. This term is often misused to indicate a primer's ability to set-off the main charge in a metallic cartridge.
BSA ... Birmingham Small Arms.
Bull ... The centre of a target, usually scoring 10 when hit. There are targets with lower value centres, such as 5, or 7, which are used for specific competitions.
Bullseye ... a) The centre of a target (see Bull above). b) A type of fast burning smokeless powder made by Hercules and particularly suited to cartridges intended to be shot by short barrelled guns.
Bullet.. The name given to the single, usually cylindrical projectile that comes out of the barrel of a gun. If there is more than one projectile, then usually the term used is 'pellet', as in a shotgun cartridge. Note: a) only the ignorant use terms such as, 'live bullets' or 'bullet heads'. b) only the ignorant use the term, 'bullets' when they mean either 'ammunition', or 'cartridges'. A bullet by itself is harmless, it is just a lump of metal and is not subject to any licensing conditions within the UK.
Bullet Catcher ... The part of the butts (see below) which actually stops and retains the fired bullet.
Bullet Mould ... A device of either steel or aluminium used to cast bullets for home reloading. The molten material (usually lead, or an alloy of lead) is poured into the mould and when set, the bullet can be removed and loaded to make a complete cartridge.
Burning rate ... The relative speed at which a propellant powder burns in comparison to other powders in a controlled combustion chamber.
Butt ... The rear end of a rifle or shotgun stock (the part that rests against the shoulder). In a handgun, the bottom part of the grip.
Butt Plate ... The plate, usually of some rubber, or plastic compound that cushions the shooters shoulder from recoil when a long-arm is fired. It is fitted onto the end of the stock.
Butts ... The name given to that part of the range which contains the target frames and the bullet catcher which traps and safely contains the fired projectiles.
Calibre ... The diameter of a projectile, or the bore of a firearm. In rifled arms this measurement is from top of land to top of land across the bore diameter. This is not always quite what it seems, for example a .38 and a .357 calibre bullet are exactly the same diameter (the same bullet in fact). Quite often the name given to a particular gun, such as a .44 magnum, is a label or a name, not an actual measurement of calibre. In fact the actual diameter of a .44 magnum barrel is .429 inch.
Calling the shot ... The action of stating the position on the target of the last shot fired, before looking through the spotting scope, or retrieving the target. This is used as a training aid, so as to enable errors to be recognised.
Cannelure ... The circumferential groove or indentation in a cartridge case and / or bullet used to hold the projectile in place and prevent its rearward movement on loading, or whilst in the magazine during recoil.
Cant ... The angle of lean from the vertical that the firearm has whilst being held by the shooter.
Cap ... An explosive device fitted over the nipple of a percussion black powder gun in order to initiate ignition of the main charge and fire the bullet.
Capping off ... The process of firing a cap on its own before attempting to load a percussion fired black powder gun, in order to clear any oil or other residue from the nipple and chamber: see Flashing pans below.
Carbine ... Usually taken to be a shortened version of a long arm (see below), held in two hands and firing a pistol calibre cartridge.
Carbon Dioxide (CO2) ... Used as a propellant for 'air' guns. It is stored on the gun in liquid form under pressure and typically will give around 180 shots per fill from a purpose designed reservoir.
Card ... Another word for target.
Cartridge ... A complete round (see below) of ammunition (see above).
Cartridge Case ... The cylindrical case, usually of brass (but other metals such as steel and aluminium have been used) that holds the primer, main charge and bullet of a complete round of ammunition. The brass case is the most expensive part of a cartridge and in the instance of centre-fire cartridges they can be reloaded.
Cast ... a) The type of bullet produced by a lead melting process. b) The process of making bullets for reloading by melting lead, or an alloy of lead. These bullets are normally not jacketed and so are only suitable for relatively low velocities. The process is quite suitable for home production.
Centre-fire ... A cartridge ignited by a primer located in the centre of the case head. The system is suitable for reloading the cartridge case and is suited to high pressure ammunition. See also the entries for Berdan and Boxer.
Chamber ... a) The part of a firearm containing the cartridge (or separate powder and ball) at the moment of firing it, normally at the opposite end of the barrel to the muzzle. b) The action of loading a round of ammunition into the gun.
Charge ... a) In the case of nitro powder and black powder, the amount, by weight, of the powder in a cartridge or load. b) In the case of Pyrodex, the amount, by volume, of the powder used. c) To fill a magazine with cartridges.
Cheek Piece ... A lateral projection from the comb of the stock. Provides additional support and contact to the shooter's cheek when the rifle is shouldered in the firing position. It is used to assist positioning the aiming eye correctly behind the sights.
Choke ... The restriction at the muzzle of a shotgun used to control the dispersion of the shot.
Chronograph ... A device to measure the velocity of projectiles fired from a gun.
Class, or Division ... The grouping into which competitors are placed according to ability, so as to allow for more even competition. Normally the classes run from, "X-Class", "A-Class", "B-Class" to "C-Class" in descending order of ability. Divisions follow the usual form of, "Division-1" to "Division-10" or as required in descending order.
Cleaning rod ... A rod, usually of plastic coated metal, longer than the barrel to be cleaned and often fitted with a ball-bearing handle. This rod takes a variety of cloths, or other attachments and pulls and pushes them through the barrel in order to clean it of any deposits.
Click ... The name given to the smallest adjustment of a sight, it is an onomatopoeic word.
Clip ... a) The name given to a (usually) metallic device to hold a group of cartridges together prior to loading them into the gun's magazine. b) An incorrect word used to describe a magazine and / or its contents.
Cock or Full-Cock ... To set the action (see above) into position for firing. On most muzzle loading firearms, the action has an intermediate position called half-cock (see below).
Comb ... The upper part of the stock where the shooter's cheek rests during aiming.
Compensator ... A muzzle brake, designed to reduce the felt effects of recoil by redirecting the escaping gases and to limit the muzzle jump on firing so as to assist rapid subsequent shots.
Count back ... The system used to break a tie between two or more competitors with the same score. It works by comparing the number of 10's shot by each person and the one with the highest number is awarded the higher ranking. If the competitors have an equal number of 10's, then the 9's are compared, then 8's etc, until the tie is broken.
Crimp.. The inward folding of a cartridge case used to retain the projectile (or shot charge in a shotgun). It can be either tapered, or rolled. Whilst a rolled crimp is more secure it cannot be used on cartridges such as the 9 mm, which headspace on the rim of the case mouth, as a rolled crimp would not provide a positive stop to the forward movement of the cartridge into the chamber.
Cross-ignition, or Chain-firing, or Flashover ... The term used to describe the dangerous result of not using grease, or another compound to seal the cylinders of a black powder revolver. When the primary cylinder is fired, lack of sealant on the other cylinders may allow them to be ignited and cause them to discharge before they are lined up with the barrel.
Crown ... The bevelled, countersunk, or rounded muzzle surface of a barrel, done thus to protect the point of exit from accidental damage.
C.U.P. ... Copper Units of Pressure. One of the standard methods of estimating the pressure inside a gun when it is being fired. Of great importance for safe reloading, as cartridge cases are quoted by their manufacturers as having a particular maximum c.u.p. which must not be exceeded.
Cylinder ... That part of a revolving firearm which holds the ammunition in individual chambers. The cylinder then rotates as the gun is used to present each round in turn to the barrel for firing.
Cylinder gap ... The gap between the front of the cylinder and the rear of the barrel of a revolver. This can be as small as 1/1000 of an inch in a high quality gun, but is usually nearer 1/100 of an inch. Some gas escapes as a result of the gap and bullet velocity is reduced, typically by about 5%.
Damascus ... An early method of making barrels out of welding together two or more rods of twisted iron and rolling them into a ribbon. This ribbon was then wrapped round a mandrel and hammered so that the edges became fused together. The result was a pretty patterned barrel of considerable aesthetic appeal and relatively little strength, for black powder use only and not to be used with nitro powder.
Density ... In the context of reloading this means, 'sectional density', or SD, which is the mass of a bullet in proportion to its cross-section. For simplicity the SD is usually calculated by dividing the weight (in grains) by the square of the diameter. As an example take a 150 grain bullet from a .308 Winchester: divide 150 by the square of .308 (.0949) to get 1581.2 and divide again by 7000 (the number of grains in a pound weight) to get .226 which is the SD.
Die ... A tool used in reloading metallic cartridge cases to resize the case to the specified dimensions, or a tool used to de-prime fired cases, or a tool used to seat bullets in cases, or a tool used to load powder into cases prior to seating the bullet.
Diopter ... Refractive power of a lens. A lens having a focal length of one metre is said to have a power of one diopter, a lens of 20 centimetre focal length has a power of +5 diopters, one of 5 metres focal length has a power of -5 diopters.
Disconnector ... Mechanical device in a semi-automatic gun that is designed to prevent the firing of more than one shot from one pull of the trigger.
Division ... See, Class, above
Dominant Eye (and Hand) ... The stronger, or 'master' eye and hand. The dominant eye is the one through which a person would usually view an object when using a telescope. The dominant hand is what the shooter would describe himself as being: for example, 'right-handed'. This causes the shooter a problem when the dominant eye is on the other side of the body to the dominant hand. In about 15% of the population the dominant hand and eye are on opposite sides. This is much less of a problem for pistol shooters than anyone using a long arm.
Double Action ... The type of firearm action whereby one pull of the trigger performs the two separate functions of, a) cocking the gun and b) firing the gun. This term is often used to refer to revolvers, but it applies to all classes of firearm (see Single Action below).
Double base ... Propellant powder in which nitro-cellulose is supplemented by nitro-glycerine.
Drift ... 1) The lateral movement of a projectile due to rotation in flight through the atmosphere. If the gun has rifling with a left hand twist, the movement will be to left and vice versa. 2) The lateral movement of a projectile due to wind.
Drop ... a) The distance that a projectile falls at any given distance from the gun. b) The distance that the centre of the butt of a long-arm is below the centre line of the barrel. Both distances are measured in inches using the Imperial system.
Dry Fire ... Firing of an unloaded firearm to practice handling and shooting techniques. This can damage some types of actions, particularly rim-fire unless a Dummy Cartridge, or Snap Cap (see below) is loaded to absorb the shock to the firing pin.
Dum-Dum ... Not a target shooting term, but mentioned for interest. It has become a slang word for any expanding bullet, especially one which has been modified by the end user and not manufactured that way. The term originated as a result of experiments done at Dum-Dum arsenal, India around 1898.
Dummy Cartridge ... Sometimes called, 'Drill rounds', these are cartridges assembled without either propellant or primer and use to test the functioning of guns and magazines without any danger of an accidental discharge. These special cartridges have to be indelibly marked to avoid fatal confusion.
Ears ... The name given to hearing protectors of whatever type.
Ears on ... The command by the Range Officer to put on hearing protection prior to commencing firing.
Ejector ... The mechanism which expels the cartridge or case from the breech of the gun. This is not the same as the Extractor (see below).
Elevation ... Vertical sight movement so as to raise the point of impact at the target.
Energy ... The force of a projectile at any given distance. The energy in ft/lbs. (foot-pounds) can be calculated from the weight of the projectile and its velocity. For example take a 150 grain bullet moving at 2800 fps (feet per second): Energy = (bullet weight x velocity squared) divided by 450,400 = 2611 ft/lbs. This formula is based on: k=½mv2 and includes allowing for converting bullet weight from grains to pounds and assumes that the acceleration due to gravity is 32.174 fps2.
English Match ... A 60 shot course of fire for .22 rimfire rifles shot from the prone position over 50 metres.
Eye Piece ... The lens of a telescopic sight nearest the shooters eye.
Explosive ... Explosives are classified as low or high according to the detonating velocity or speed at which they change from being a solid or liquid to gas and other pertinent characteristics such as their shattering effect (or brisance). An arbitrary figure of 3300 fps is used to distinguish between burning / deflagration (low explosive) and detonation (high explosive). A propellant is said to burn at less than the speed of sound (approximately 1100 fps). Within the UK the possession and use of any explosive is subject to having the necessary licence.
Extractor ... The device which extracts, or removes the cartridge or cartridge case from the chamber of the gun. This is not the same as the Ejector (see above).
Eye relief ... The distance, usually about 4 inches, between the shooter's eye and the rearmost part of the sights. This distance is important both for good vision of the target and to prevent injury when shooting a gun with significant recoil. In the case of Telescopic Sights there are special models available for use with hand guns which have extended eye relief, so as to allow their use at about 18 inches from the eye.
Felt recoil ... The way that a shooter actually feels the recoil, or 'kick' of a gun when it is fired. In general, guns firing ammunition with a nitro powder will have a sharper, more jarring recoil that those firing black powder. Guns with some form of automatic, or semi-automatic loading mechanism feel less harsh than those without, due to the operation of the gun 'spreading' the recoil out over a longer time period.
Fg, FFg, FFFg, FFFFg ... Grades of size of black powder particles, from coarsest to finest. FFFFg is mainly used as a priming powder for flintlocks, wheellocks and matchlocks. Also see 'Swiss' below.
Firearm ... Any gun which uses the combustion of a propellant or an explosive to discharge a projectile.
Firearms Certificate (FAC) ... The necessary permit to hold any firearm or ammunition in the UK, it lasts for 5 years before renewal, a simpler form of licence is required for shotguns.
Fireform ... The process of changing the shape (and volume) of a cartridge case by firing with (normally) a light load in the gun in which it is to be used. This is a means of improving accuracy and functioning by matching the case to the exact size of the chamber of a particular gun.
Firing Pin ... The part of a gun's action which actually strikes the primer so as to set it off and initiate firing the cartridge's main charge of propellant.
Firing Point ... The physical position from which shooting takes place, they should be numbered consecutively from 1 upwards with contrasting colours i.e. if 1 is painted black, 2 should be white, etc.
Flash hole ... 1) The small diameter hole through which the 'flash' from the priming charge of a muzzle loading gun travels to ignite the main charge. 2) The small diameter hole (Boxer) or holes (Berdan) through which the flame from the primer of a centre-fire cartridge passes to ignite the main charge in the cartridge case.
Flashing Pans ... The action before the commencement of shooting, of firing off a priming charge of powder from the pan of a matchlock, wheel lock or flintlock muzzle loading gun in order to clear any oil or other residue from the flash hole and chamber, before loading the main charge: see Capping off above.
Flash in the pan ... a) What happens when the priming powder in the pan of a matchlock, wheel lock or flintlock gun goes off without igniting the main charge. b) A short-lived enterprise of some sort.
Flintlock ... A muzzle loading firearm with its powder charge ignited by a flint striking a metal surface (the frizzen) to produce sparks which ignite fine priming powder, which in turn sets off the main charge.
Follow-through ... Staying in the same position after pulling the trigger or continuing the swing in firing at a moving target. This is done in order to assist in, 'calling the shot' (see above).
Foot-pound ... The energy required to lift one pound through a distance of one foot (strictly speaking this is only true at the earth's surface).
Forcing Cone ... The tapered section of a shotgun or revolver barrel where the pellets or bullet is guided into the bore.
Fouling ... The deposits that build up in the barrel of a gun after it is fired. Fouling can be soft and harmless carbon residue, or more persistent lead, or copper, which is detrimental to accuracy.
Fouling Shot ... The process of firing a shot off before starting trying to shoot accurately, so as to remove any oil from the barrel and to coat the bore with a typical layer of residue. This process is most important for muzzle loading guns in order to obtain consistent accuracy.
f.p.s. (or, fps) ... Feet per second, the standard measure of projectile velocity in the Imperial measurement system.
Free Bore ... The unrifled portion of the bore, if any, in front of the chamber, it can be up to about a half the length of the barrel. Not much used these days and normally only for low powered cartridges such as the .22 rimfire.
Free Pistol ... A .22 calibre target pistol which is 'free' of most constraints as to barrel length, sight radius, weight etc.
Free Rifle ... A .22 or centre fire rifle which is 'free' of most constraints in the same way as a free pistol.
Frizzen ... The upright steel plate in a flintlock gun which is struck by the flint in order to produce the sparks for igniting the priming powder. Note: the sparks come from the steel NOT the flint!
Ft.-lb, or ft/lb ... Foot-pound, the standard unit of energy in the Imperial measurement system, used as a measure of the energy contained in a bullet in flight.
Full-bore ... Generally taken to mean centre fire calibres, especially those of .22 and greater: synonymous with the term, Big bore.
Full-Cock ... The action of setting the action (see above) into the ready to fire position. See half-cock and cock.
Full Metal jacket ... A jacket, usually of copper completely covering a bullet, so as to leave no lead exposed. Much used for military ammunition as it helps to comply with the Geneva Convention on Land Warfare, which specifies that expanding ammunition must not be used against human targets. It also allows the bullet to be driven much faster than a plain lead projectile.
Gain twist ... A system of rifling with the pitch increasing towards the muzzle.
Gas cutting ... What happens when using high pressure cartridges in a revolver and the gasses literally cut the metal of the top strap of the frame when they escape through the cylinder / barrel gap.
Gauge ... a) A plug device used to accurately score a shot target, it has a diameter exactly that of the calibre used and when inserted into the target shows the edge nearest to, or in some cases, farthest from, the centre. b) In American usage it is the bore, or calibre of a shotgun or other smoothbore gun.
Grain ... a) A unit of weight used to measure powder charges and bullets. By definition it is 1/437.5 of an ounce avoirdupois and therefore there are 7000 grains to the pound. b) The natural pattern of wood.
Groove ... The sunken part of rifling.
Groove diameter ... The distance across the bore of a rifled barrel from the bottom of one groove to the bottom of the one opposite, this is easily measured by means of a lead slug. In the case of a barrel with an odd number of grooves this is measured by driving a soft lead slug into the barrel and then measuring the slug's diameter over a land-to-groove cross section and then subtracting the bore diameter. The next step is to double this figure and add it to the bore diameter to get the groove diameter.
Group ... The pattern of shots on a target.
Guncotton ... Nitro-cellulose: a form of smokeless propellant.
Gunpowder ... An explosive made up of 70% saltpetre, 15% sulphur and 10% charcoal. It has been used as both an explosive for blasting and mining operations as well as to fire projectiles from firearms. Also known as, Black-powder: see above
Half-Cock ... a) The safety position for a matchlock, wheel lock, flintlock or percussion gun. The hammer is moved to a halfway position from which it cannot be released by the trigger and the gun can then be carried loaded in safety. b) "To go off at half-cock" means to start an abortive, or failure-ridden enterprise and it is derived from the unfortunate practice of early guns to slip off the half-cock position and fire prematurely. See, cock and full-cock above.
Hammer ... a) The part of the action which drives the firing pin to strike the primer in a cartridge gun. b) the part of the action which carries the flint for a Flint-lock gun. c) The part of the action which strikes the cap in a Percussion gun: see Serpent below for Matchlock guns.
Hang fire ... A term applied to an excessive delay in ignition of the main charge after the primer has fired, this is mainly a problem for black powder muzzle loaders and especially Matchlocks.
Hard hitting ... A nonsense term used by the ignorant when describing guns so as to show how little they know or understand about shooting in general.
Headspace ... This is the distance from the breech face to that part of the chamber which stops the forward movement of the cartridge case. Different cartridge designs obtain their headspace in different ways. A rimmed case, such as a .22 rimfire uses the case rim to position the cartridge within the chamber, whilst a rimless cartridge, like the 9 mm Parabellum uses the rim of the case mouth, seating on an annulus in the chamber (this means that 9 mm cases must be both of exact length and not use a rolled crimp to hold the bullet in place).
Headstamp ... The manufacturers marks stamped into the primer end of a metallic cartridge case giving various details of its construction, such as calibre, maker, load, date of manufacture, etc. There is no universal standard for this information and its value and content can vary widely.
Inertia Firing Pin ... A firing pin which is shorter than the guide in which it travels to strike the primer. It is propelled sufficiently quickly from its resting position to cover the distance from the hammer to the cartridge primer and then to detonate the primer, due simply to its own inertia.
Inner-10 ... The name given to a smaller ring enclosed by the 10 ring on a target. Normally the Inner-10 does not have a score value, it is used as a tie-breaker between competitors with an identical numerical score; the one with the higher number of Inner-10's being the winner: see below for X-Ring.
International Shooting Union (ISU) ... See UIT and ISSF below.
International Shooting Sport Federation (ISSF) ... The successor to both the UIT and the ISU, it is the regulatory body (based in Munich) that controls all international target shooting with Airgun, Crossbow, .22 rimfire and Centre fire, both rifle and pistol.
Inward gauging ... The scoring process whereby the edge of the bullet hole nearest the centre of the target determines its value. In this method the shot hole has only to touch (not cut) the next higher scoring ring to be awarded the higher value: see also, Outward gauging and muzzle-loading gauging below.
Iron Sights ... See Metallic sights below.
Jacket... A covering over the lead core of a bullet. Usually this cover is made of copper and can be either complete (see Full Metal Jacket above), or partial. If partial, it can leave either the nose or the tail of the bullet exposed. An exposed nose is much used in hunting, as it allows the bullet to expand and transfer more of its energy to the game being shot. All jackets allow the bullet to be fired with greater velocity than plain lead could withstand.
Journee's Formula ... The empirical formula used to calculate safe distances for shotgun pellets. It says that the maximum range in yards for a round pellet is 2200 times its diameter in inches.
Land ... The raised portion of rifling.
Lapping ... The process of repeatedly passing a lead 'slug' (usually a wadcutter bullet mounted on a cleaning rod) through the bore of a gun barrel in order to lap, or polish it. The polishing is assisted by means of dipping the slug in a mild metal polish, such as Brasso. This method is used to remove rough spots from the bore which can give rise to leading: see Leading below.
Lead... An elemental metal from which the majority of bullets are made. Dull grey in colour, it is highly malleable with a low melting temperature and is easily alloyed with other metals, such as tin in order to make it harder. Plain lead bullets are limited to about 700-800 fps velocity, those of an alloy of lead, tin and antimony can go up to about 1400 fps, but beyond that velocity, they must be jacketed in order to prevent leading: see Jacket above and Leading below.
Leading ... The deposition of lead in the bore of a gun due to the passage of lead projectiles (pronounced: "ledding"). Often caused by firing the bullets at too great a velocity, or by a slight roughness in the barrel, stripping a sliver of metal off as they pass: see Lapping above.
Leade ... The short unrifled section of the bore, if any, in front of the chamber, into which the bullet's nose is introduced (pronounced: "leed").
Let-off ... A somewhat vague term used to describe the release of the sear when the trigger is pulled to fire the gun. A 'crisp' let-off denotes a sudden release, like the click of a light switch, a 'rollover' let-off denotes a rather more vague firing point.
Linatex ... A self-healing, or self-sealing rubber sheet material, used in the UK to reduce splatter from bullets impacting on the bullet catcher: see Anti-splash and Bullet Catcher above).
Load ... a) To place a round of ammunition in a firearm chamber or magazine. b) A specific type or composition of ammunition.
Lock ... The firing mechanism of a muzzle loading firearm.
Lock, Stock and Barrel ... a) The three main parts of a muzzle loading gun. b) A general term used to mean everything associated with some enterprise.
Lock time ... The time taken from the release of the sear by the trigger to the moment the primer is struck, usually very short, less than 2 milliseconds being the aim.
Long-arm ... Any gun held in two hands with a butt piece held against the shoulder.
Machine Rest ... A device for securely holding a gun in a consistent position so as to allow accuracy testing of gun and ammunition: see Bench Rest above.
Magazine ... a) A device for holding ammunition ready for loading into the chamber of a repeating firearm. b) A storage room for ammunition and, or explosives.
Magnum (Mag) ... a) A loose term used to signify a cartridge, either rimfire or centre fire of any size, for either rifle or pistol, which is loaded to higher than normal pressures. b) A term used to describe firearms which are designed to fire magnum ammunition e.g. a Smith & Wesson model 29 .44 Magnum revolver.
Malfunction ... The name given to any kind of inability to discharge a shot when required. Malfunctions come in two types, Allowable and Non-Allowable. Depending on the type of competition there may not be any allowance for malfunctions at all. Allowable malfunctions are those due to gun failure, ammunition failure and target failure. Non-Allowable malfunctions are due to forgetting to load the gun, forgetting to insert the magazine, not releasing the trigger enough to allow the next shot to load etc. The basic rule is that if the malfunction was attributable to the shooter, then it is not allowed, if it was due to some other, external factor over which the shooter had no control, then it is allowed. An allowed shot may be retaken under the same conditions as the original shot.
Martini Rifle ... A type of falling block action used in single shot guns. In the case of BSA .22 rimfire rifles the block is hinged at the rear. Viewed from the side with the breech open these guns bear a passing resemblance to Winchester underlever repeating centre fire rifles.
Match ... a) A string soaked in nitrate so as to burn slowly and steadily without going out in wind, used to fire a Matchlock gun. b) A shooting competition.
Matchlock ... A muzzle loading firearm which is fired by means of a slowly burning match being applied to a flash hole by means of the trigger.
Mean Point of Impact, or, MPI ... The mathematical centre of a group of shot holes on the target.
Metallic Sights ... A somewhat loose term used to describe non-optical sights, especially open sights as fitted to handguns. Also known as, Iron sights.
Metplat ... The diameter of the tip of a projectile. This is a somewhat difficult term to define exactly, but is usually taken to mean that part of the projectile after the dramatic change in radius as the tip is approached. In a full wadcutter bullet, the Metplat and the calibre are one and the same diameter.
Minute of Angle (MOA) ... The radial distance represented by 1/60 of a degree (there being 360 degrees in the circumference of a circle). The MOA is used in target shooting as a handy reference of accuracy and for sight adjustment. At a range of 100 yards 1 MOA represents a distance of 1.0472 inches (or approximately 1 inch). Sights are normally calibrated in fractions of a minute, a typical .22 target rifle with aperture sights will have 1/8 minute adjustments i.e. at 100 yards range, 1 click (see above) of the sight will move the point of impact 1/8 inch. General purpose telescopic sights normally have 1/4 minute adjustments.
Minie ... A cylindrical shaped bullet used in muzzle-loaders. It has a pointed tip and a hollow base which spreads to give a good seal to the barrel in a similar manner to a pellet in an airgun when it is fired.
Mirage ... The observed apparent movement and or distortion of a target due only to temperature created air disturbance between the shooter and the butts. Usually, but not always this is an outdoor, long range phenomena.
Monte Carlo Stock ... A stock with a raised comb which provides elevated eye alignment when using a telescopic sight, which stands higher above the bore line than metallic sights.
Musket ... The name of a shoulder fired muzzle loading (and usually) smoothbore gun held in both hands.
Muzzle ... The end of the barrel from which the projectile exits.
Muzzle blast ... The blast, or shockwave felt by a shooter and observers when the bullet exits from the barrel.
Muzzle Brake ... A device consisting of various vents either attached to, or integral with the end of the barrel which is designed to reduce the amount of felt recoil and muzzle jump. See compensator above.
Muzzle Crown ... The process whereby the muzzle is rebated, or 'crowned' so as to provide some measure of protection from accidental damage to the bore of the barrel.
Muzzle energy ... The energy, measured in Foot-Pounds (ft/lb) that a projectile contains when it leaves the barrel of a gun.
Muzzle Flash ... The flash, caused by unburned powder burning-up in free air after the bullet has left the barrel.
Muzzle jump (or, climb) ... The vertical movement of the muzzle on firing the gun caused by the centre of the barrel being higher than the centre of support for the gun.
Muzzle Loader ... Any gun which is loaded from the muzzle end, usually by means of a separate powder charge, with the bullet seated afterwards. Muzzle loaders can be, Matchlocks, Wheel Locks, Flintlocks, or Percussion fired. See Breech loader, above.
Muzzle Loaders Association of Great Britain (MLAGB) ... As the name implies, the group that deals with muzzle loading regulation and competition within the UK.
Muzzle Loaders Association International Committee (MLAIC) ... The body that governs all International muzzle loading competitive target shooting.
Muzzle-Loading gauging ... The scoring process whereby the centre of the bullet hole nearest the centre of the target determines its value. In this method, the shot hole has to cut the scoring ring to be awarded the higher value. This scoring process allows competitors using different calibre guns to compete on an equal basis without the use of scoring gauges: see also, Outward gauging below and Inward gauging above.
Muzzle velocity ... The velocity of a projectile as it leaves the barrel of a gun, normally this is the maximum velocity reached (some military ammunition can be fitted with a secondary charge which can be fired later on to act as a booster).
Nature ... What the British army calls bullets, pellets, rockets and shells. See also the entry for, projectile.
Nipple ... A drilled cone shaped part of a black powder gun, fitted at the end of the barrel, or chamber at the closed end and used to hold the percussion cap(s) needed to fire the main charge(s).
Nitro ... a) Short for Nitro-cellulose, the standard form of smokeless propellant used today for cartridge guns of all types b) A term used to describe both the propellant nitro-cellulose and the guns themselves that have been made to use it.
Nitro-cellulose ... Otherwise called guncotton. This is the basis of all modern smokeless propellants, it is made by dissolving cotton in nitric acid (do not try this at home).
N.R.A. or NRA ... National Rifle Association (of Great Britain). The body that deals with full bore rifle and pistol target shooting in the UK.
N.S.R.A. or NSRA ... National Small-bore Rifle Association. The body that deals with .22, airgun and crossbow target shooting in the UK.
Object lens ... The lens of a telescopic sight (or any optical device) nearest the object being viewed.
Obturation ... The expansion of a cartridge case on firing to seal off the chamber and prevent gases from escaping.
Ogive... The curved portion of a projectile between the cylindrical radius and the Metplat (diameter of the tip of the projectile).
Olympic final ... A 10 shot shoot-off between the top 8 shooters in an ISSF competition. Scoring is done to 1/10 of a point for each shot, with a maximum score for a perfectly central shot of 10.9 and thus a maximum total score for all 10 shots of 109.
Open Sights ... See metallic sights above.
Outward gauging ... The scoring process whereby the edge of the bullet hole furthest from the centre determines its value. In this method, the shot hole has only to touch (not cut) the next lower scoring ring to be awarded the lower value: see also, Inward gauging and muzzle-loading gauging above.
Over-travel ... The amount of rearward travel of the trigger after the release of the sear.
Pan ... That part of a matchlock, wheel lock or flintlock muzzle loading gun that holds the priming powder next to the flash hole so that the main charge can be ignited by it.
Parabellum ... a) A term synonymous with the 9 mm pistol calibre cartridge. b) A contraction of the quotation from Vegetius in the 4th century AD, the original Latin of which is, "Qui desidererat pacem praeparet bellum", or in English, "If you wish peace, prepare for war".
Parallax ... The apparent shift in position of a viewed object attributable to the difference between two separate and distinct points of view. A major problem for users of telescopic sights. In order to be able to use such sights accurately they must have a parallax adjustment to compensate for different ranges: note this is not the same as focussing. If a telescopic sight does not have an adjuster ring near the object lens, then almost certainly it does not have parallax adjustment.
Patch ... a) A small piece of leather or cloth that is greased and placed around a bullet before ramming it down the barrel of a muzzle-loader so as to hold it firmly in place and prevent it rolling out. b) A piece of cloth drawn through the bore of a firearm to clean it. c) The action of covering bullet holes in a target using small adhesive disks so as to extend its useful life.
Pellet ... Either an airgun projectile, usually of lead, or a component of a shotgun cartridge which is fired out of the gun. Normally shotgun pellets are round balls of lead, or often these days, of steel.
Percussion (gun and / or method of firing) ... The name given to firing a gun by means of a percussion cap placed over the flash hole (called a 'nipple' on a percussion gun). Percussion guns are normally muzzle loaders and can be either single shot, or multi shot like the first Colt revolvers ('Six Shooters').
Pistol ... A relatively short gun, usually under 24 inches long and held in one or both hands. Typically it will fire a reduced load cartridge compared to a rifle and normally in modern construction the barrel will be rifled to improve accuracy. See also the entries for Automatic and Revolver.
Plinking ... An American term for casual, non-precision shooting, usually aimed at informal targets such as tin cans etc.
Police Pistol 1 (PP1) ... A competition where 12 shots are fired (in two groups of 6) at a man-sized target at 25 metres in two minutes (including reloading). This is followed by 12 shots, one shot every 2 seconds with 5 second intervals, at 15 metres, followed by 6 shots, two shots at a time in 2 second bursts with 5 second intervals, at 10 metres. Total number of shots is thus 30 and there are no allowances for any kind of malfunctions.
Position ... The position of the body of the shooter when firing, for competition under ISSF rules, this will be either, standing, kneeling or prone (lying face down): see Prone, Standing and Kneeling below. Other positions used for non-ISSF shooting are, sitting, which is quite rare and supine (lying on the back) which is used for long range rifle shooting.
Possible, Poss, Highest possible score, HPS ... The highest possible score on competition targets, normally this has a value of 100 when shot to international rules. Exceptionally, in the case of a10 shot Olympic Final, where scoring is done in 1/10 points, the maximum is 109.
Primer.. a) An explosive compound either all around the rim of a rimfire cartridge case, or in a centrally mounted cap (usually replaceable) for centre fire cartridges. It is used to set off the main charge. b) The small charge of fine grained black powder used to ignite the main charge of a Matchlock, Wheel Lock or Flint Lock gun.
Progressive ... Name given to a type of reloading press whereby one pull of the operating lever competes one stage of the process and allows the press to be moved to the next stage.
Projectile ... The name given to any item coming out of the barrel of any type of gun when it is fired. See also the item for, nature.
Proof ... The process of proving a gun safe for use, usually done by firing a special test cartridge which will apply at least 30% more pressure to the gun than its quoted limit. In the UK this work is carried out at either the Birmingham, or London Proof Houses.
Proof mark ... The stamping on the barrel of a firearm to how that it has passed the proof test. In the case of a revolver, each chamber is separately proofed. Note that European countries accept each others proof system, but guns imported from the USA into the UK have to be proofed before they can be sold (this is because there is no universal Federal system of proof across the USA). In the UK, currently a new proof mark for nitro powder from Birmingham is shown as, "BNP" and from London as, "NP"
Prone, Standing and Kneeling, PSK, Three Positional, 3P ... As the name implies, a competition which is shot using three different body positions to support the gun. It is for rifle only and shot at 50 metres for international competition over a total of 60 shots, 20 from each position and is for the .22 rimfire calibre using single shot guns.
Propellent... Any substance which can be used to operate a gun by burning in a controlled manner. In the UK propellants are not subject to the laws governing explosives and so can be freely bought by anyone over the age of 16 without a licence. Propellants are substances that support the spread of combustion at speeds below that of sound (approximately 1100 fps). They cannot be sent through the post.
Proving safe ... The action of demonstrating that a gun is not loaded.
Pyrodex ... A Black powder substitute: in the UK it is classed as a propellant and is thus free of licensing restrictions. It is corrosive to steel and guns have to be cleaned thoroughly after use.
Ramrod ... A rod of non ferrous construction used to 'ram' the ball (or bullet) down the barrel of a muzzle loading gun so as to seat it firmly on the charge of black powder. It must be made of a material which cannot strike sparks off the steel of the barrel. The ramrod can also be used to determine if a muzzle loading gun is actually loaded, by marking it so that one can tell when it reaches the end of the chamber and thus indicates that there is no charge present.
Range ... a) The distance from the firing point to the target. b) The location, either indoors or outdoors at which shooting takes place.
Range Commands ... The instructions given by the Range Officer to the shooters, detailing how the current course of fire is to be carried out. These can vary from the very simple, "Fire" and "Cease Fire", to quite elaborate instructions, depending on the event.
Range Officer, RO, Range Conducting Officer, RCO ... The person in charge of shooting on the range.
Range Safety Certificate ... The certificate supplied by the Army (in the UK), stating the maximum calibre, muzzle velocity and muzzle energy that can be used and over what distances and from what firing positions for any given Range. It is not permitted to operate a Range without this document having been issued following a formal inspection of the premises by the Army.
Receiver ... The part of a breech loading firearm comprising of the chamber end of the barrel with the loading / unloading port.
Recoil ... The rearward movement of a gun when fired. Note that it is in general more comfortable to fire a gun with heavy recoil from the standing, rather than the prone position. See also: felt recoil.
Reloading ... The practice of reloading brass cartridge cases with primer, propellant and bullet so as to use them again. With light target loads straight-walled brass cartridge cases can be reloaded 20+ times. Note that other materials than brass have been used for cases, but brass is the only material to date which has demonstrated sufficient flexibility and elasticity to allow successful reloading of high pressure ammunition.
Reticule ... The aiming device built into a telescopic sight, usually in the form of cross-hairs for target shooting purposes. There are many different forms of reticule for sporting use.
Revolver ... A pistol with a revolving cylinder that can hold (usually) 5 or 6 rounds. They can be either front loaded black powder guns, or fire metallic cartridges.
Rifle ... A long gun with a rifled barrel that is held in both hands and is further supported by the shoulder, normally the shooters cheek rests on the rear stock of the gun.
Rifling ... Spiral grooving in the bore of a firearm that is used to spin-stabilise the projectile and thus improve its accuracy after leaving the barrel. Rifling can be either clock, or anti-clockwise in direction and can have either an even, or an odd number of grooves. Pistols can and usually do have rifled barrels, the system is not unique to 'rifles'.
Rimfire ... A system of priming a cartridge case where the primer is held in the rim of the case and is set off by the cartridge case rim being struck and crushed. The cases cannot be reloaded and the system is only suitable for low pressure ammunition such as the .22 commonly used for target shooting.
Round... A complete item of ammunition with all components present to allow the firing of one shot. It can take several forms: a) for modern metallic ammunition it consists of a cartridge case with fitted primer, main charge and projectile(s) all assembled together, that is all the components together required to fire one shot. Or b) for muzzle loading guns it refers to all the required components either in loose, or part assembled form to fire one shot (see glossary for description of individual items).
Round nose... A bullet with a rounded head such as used in most .22 rimfire target cartridges. These bullets need the use of a scoring gauge on the target in order to determine the true value of the shot, due to the way that the hole closes up after they have passed through the paper.
SAAMI (Sporting Arms and Ammunition Manufactures Institute) ... The American body that quotes many of the data used in reloading, such as the maximum working pressures for cartridge cases.
Sabot ... A lightweight carrier in which a sub-calibre projectile is carried: it comes from the French for a clog or shoe. The term, Sabotage, comes from the practice, during the Industrial Revolution, of disenchanted workers throwing their sabots into the new-fangled machines in order to break them.
Safety (Safety Catch) ... A mechanical device to reduce the likelihood of accidental discharge of any gun to which it is fitted (provided that it has been engaged at the time): not much used in target shooting circles.
Sear ... The part of a gun's action that is 'tripped' by the trigger to release the hammer, or firing pin and initiate firing the cartridge.
Semi-automatic ... See the entry for, automatic, above.
Semi-wadcutter ... A bullet shape halfway between roundnose and wadcutter. Often used in semi-automatic guns to facilitate easy feeding of ammunition from the magazine to the chamber. The shape of the bullet head makes for a neater hole that is easier to score than that of a roundnose.
Serpent ... The part of the action of a Matchlock gun which carries the match to the pan when the trigger is pulled in order to ignite the priming powder and hence fire the gun.
Set Trigger ... A very light trigger that is prepared, or set, by the operation of either another lever, or by manipulating the trigger itself.
Sectional density (SD) ... The ratio of the bullet mass to the square of its diameter in inches, so therefore SD=bullet weight in pounds / bullet diameter in inches2.
Sight ... Device fitted to a gun to assist the aiming of it in relation to a target. Non optical sights are in two parts, the fore sight mounted at the muzzle end and the rear sight mounted as far to the rear as practical.
Sight adjustment ... 1) With adjustable rear sights, move the sight adjuster in the direction you wish the shot to go on the target. To move the shot right, move the rear sight to the right etc. Usually sights have right-hand threads on their adjusting screws and this means that clockwise = up on the elevation adjuster and clockwise = right on the lateral (or 'windage') adjuster. 2) With adjustable front sights, move the sight adjuster in the opposite direction that you wish the shot to go on the target.
Sighting picture ... The appearance of the sights when they are correctly aligned with each other before the target is in view. See also, aiming picture.
Single Action ... The type of firearm action whereby one pull of the trigger performs the single function of firing the gun. This term is often used to refer to revolvers, but it applies to all classes of firearm (see Double Action above).
Skid shot ... A shot that hits a turning target whilst it is turning and thus produces an elongated hole. Depending on the length of the 'skid' the shot may be discounted from the total score and thus count as a miss.
Small-bore ... Generally taken to mean .22 rimfire.
Smokeless powder ... A term usually used to refer to nitro powders. Note that nitro is not totally smoke-free, but compared to black powder (gun powder) it is a huge improvement.
Smoothbore ... A gun which is not rifled and whose barrel is completely 'smooth' all the way from breech to muzzle. The projectile is not spin-stabilised and hence the guns are relatively inaccurate. The most common modern gun that is a smoothbore is a shotgun.
Snap Cap ... An inert cartridge with a spring loaded primer, used to check gun functioning and for dry fire practice: see Dry Fire above.
Spotter ... A companion to the shooter on the firing point, who undertakes recording the accuracy of shooting and can advise on wind conditions, especially for long range shooting.
Spotting Scope ... A telescope on a stand, used to observe the position of a shot on the target from a distance and without having to retrieve it. This is done either by directly viewing the hole, or watching the signals of a marker in the butts (especially at long ranges). Normally a magnification of between 20 and 30 times is used.
Swaging ... A process of manufacturing bullets out of lead wire using great pressure to cut and 'swage', or 'squeeze' the bullet into shape. Swaged bullets can be jacketed. This is not usually a practical proposition for home manufacture, due to the large forces involved.
Swiss ... Very fine black powder, finer than FFFFg and used as a primer in muzzle loading guns.
Target ... The object, usually made of thin card, at which shooting is directed and which enables scoring of the results.
Telescopic Sight ... A sight built into a telescope and designed such that the reticule and the target are in focus at the same time. For target shooting purposes the sight must have parallax correction to be of any use.
Throat ... The unrifled part of the bore immediately in front of the chamber.
Throat erosion ... The erosion of the throat area caused by the hot gasses of the propellant burning away the metal and limiting the barrel's useful life. This is mainly a problem of high pressure rifle cartridges.
Torque ... The tendency for the gun when fired to twist in the opposite direction to the rifling. This can be a real problem for pistols when shot single handed, less so for rifles.
Trigger ... The device normally operated by the shooter's index finger that initiates the firing of a gun.
Trigger Shoe ... A device which fits over the standard trigger so as to offer a wider surface to the trigger finger and thus give the impression of reducing its apparent weight.
Trigger stop ... A device to limit the over-travel of a trigger when pulled: see over-travel above.
Trigger Weight ... a) The weight that a trigger must support to comply with competition rules e.g. for air pistol it is 500 grams, for air rifle there is no lower limit as long as the gun is safe to use. b) The weight (often made of brass) used to check a competitor's trigger before passing the gun as complying with the rules for shooting.
Turning Targets ... A device, usually electrically operated that twists a target through 90o very rapidly so as to present the target to the shooter. Used in timed fire events and controlled by an electronic timer.
Twist ... The turn of the rifling. For example a barrel with a 12 inch twist means that for every 12 inches of movement down the barrel towards the muzzle, the projectile makes one complete turn.
Two stage trigger ... A type of trigger which has (normally) about half the trigger weight to fire the gun taken up by a relatively long rearward movement and the remainder by a crisp sudden let off. This is a device to enable easier shooting, by giving the shooter some idea as to how much weight has been taken up before the shot is fired.
Union International de Tir (UIT) ... The old (French) name for the International governing body of target shooting. It means, International shooting union: see also ISU and ISSF above.
Velocity ... The speed of a projectile after it has left the barrel, usually quoted as so many, fps (see above).
Wad ... A disk, or series of disks of soft material used to seal the projectile and powder into the cartridge and or, gun.
Wadcutter ... A bullet with a flat, circular head the same diameter all the way along its length. Especially used in target shooting as they punch a neat round hole the same diameter as the bullet and thus make scoring easier.
Wheel Lock ... An early type of muzzle loader lock system which came before the flintlock. A spring driven wheel was released by the trigger. This spinning wheel struck a shower of sparks off a lump of pyrite which led to ignition of the priming charge and hence the main charge.
Windage ... The lateral sight adjustment so as to move the point of impact sideways on the target.
Wind-doping ... The ability to read the changing wind conditions at long range outdoors, so as to be able to compensate for them on a shot-by-shot basis.
Wiping-out ... A somewhat vague term, used to indicate the removal of oil from a muzzle loading gun before attempting to load it for the first time at a shoot and also the quick clean and squirt of oil down the barrel at the end of a shoot before packing up to leave the range.
X-Ring ... The name given to a smaller inner ring enclosed within the 10 ring and used as a tie-breaker. Normally the X-Ring does not have a numerical value: see also 'Inner 10' above.
Zero ... The sight settings in windage (lateral) and elevation (vertical) where the point of aim and the point of impact coincide. It can be set to any range desired.
Zoom ... A term used to describe variable magnification optical devices. In the case of telescopic sights a magnification of about 4x is the maximum for shooting from the standing position, 10x for prone shooting and anything up to 30x and above, for bench-rest shooting.