Glossary of target shooting terms from K to Z
(shooting terms A to J)
as applying to
Marple Rifle and Pistol Club (MRPC)
This glossary is of necessity not exhaustive, it concentrates mainly on the terminology of those aspects of shooting practised by members of Marple Rifle and Pistol Club (MRPC) within the UK, it is not intended to be a complete work of reference. If you can think of any items that should be included, please email your suggestions to: enquiries
Where there is more than one way of spelling a term, the most usual is given first, for example: fullbore, instead of full-bore, or Full Bore. This page covers glossary terms from K to Z, for terms from A to J (including numerical terms), take the link.
Keyhole ... 1) Elongated hole made in a target by a bullet that is tumbling in flight and hence striking the target other than point first. Caused by inadequate rotational stabilization of the bullet, usually due to insufficient barrel twist or too low a velocity for the calibre. 2) An example of good shooting when successive shots are so close together as to form a 'keyhole' shaped group on the target.
Kneeling ... Kneeling is a very stable shooting position, used mostly in rifle shooting. The degree of steadiness achieved approaches that of prone shooting, but it takes a great deal of practice to get the best results. The position is with one knee on the ground and the other foot flat on the floor, normally a roll of firm material is used under the instep of the bent leg for support. A sling is often used with rifles for further support in a similar manner to prone shooting.
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.
Lever Action ... Usually a repeating type of action with a reciprocating breechblock powered by a finger operated lever. Commonly these guns have a tubular magazine held parallel to and under the barrel; a common sight in 'cowboy' films.
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 and Load ... A Range Command meaning to close the breach and chamber a cartridge prior to commencing shooting.
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 two milliseconds being the aim.
Long-arm ... Any gun held in two hands with a butt piece held against the shoulder.
LR Rifle ... Both LR rifles (Lever Release) and MARS rifles (see MARS Rifles below) are now effectively banned in the UK.
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.
Macrae Handicap system ... A handicapping system for competitions that tries to ensure that all participants have an equal chance of winning by recognising that it takes more effort for a skilled shot to improve their scores than a beginner. It is available to use in the form of tables and are rather like a set of mathematical Log tables in appearance.
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 centrefire 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. c) A bottle of champagne or other drink of 1.5 litre capacity i.e. with a volume equal to two normal bottles.
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.
MARS Rifles ... Both MARS (Manually Activated Release System) and LR rifles have a gas system that automatically ejects the fired case and pushes the working parts to the rear where they lock open. A MARS rifle then will allow the working parts forward by pulling the trigger; a second pull fires the next shot and the sequence repeats. An LR rifle has a separate control, the release lever, that allows the working parts forward to make the rifle ready for the next shot. MARS rifles are almost all the CZ58, imported and distributed by Caledonian Arms. Most LR rifles were made by Southern Gun Company Ltd and superficially resemble an AR-15. Both MARS and LR rifles now require a Section 5 FAC and hence are effectively on the banned list in the UK (with effect from 9 March 2021).
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 under lever repeating centrefire 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.
Mil ... An angular unit of measurement much used by the army and equal to 1/6400 of a complete revolution (thus there are 6400 Mils in 360 degrees and so 1 Mil equals 0.05625 degrees). One Mil subtends an arc of one metre at a distance of one thousand metres. Some telescopic sights, especially those intended for military use, are calibrated in Mil and are referred to as "Mil-Dot" scopes. Given that the shooter can accurately estimate the size of the target (for example a particular type of vehicle), the gradations in the reticule of the Mil-Dot telescopic sight can then be used to estimate the distance (or vice-versa). See also MOA below.
Millisecond ... One thousandth of a second (1/1000 second).
Minute of Angle (MOA) ... An angular unit of measurement equal to the radial distance represented by 1/60 of a degree (there being 360 degrees in one revolution and therefore 21,600 minutes). 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. See also Mil above.
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 when it is fired; in a similar manner to a pellet in an airgun.
Ministry of Defence Ranges (MOD Ranges) ... The armed forces of the UK owned shooting ranges, especially those ranges which allow their use by civilian clubs to practice outdoor target shooting. There is an (over 130 year long) arrangement within the UK, which allows civilian clubs to use MOD ranges when they are not being used by the armed forces. Being military ranges they usually have a high value Range Safety Certificate, which means that full loads can be used in the guns.
Mirage ... The observed apparent movement and or distortion of a target, due only to temperature created air disturbance between the shooter and the target. 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, flintlock which is usually, but not always, a smoothbore gun held in both hands. Note that 'Rifled Muskets' have been made and the main distinguishing feature of such a gun to distinguish it from a true muzzle loading rifle is that it will have a short stock and thus be intended to be fired from the standing position.
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 when it comes into contact with a hard object.
Muzzle energy ... The energy, often 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 for each calibre: 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 fullbore 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.
Ocular Lens ... The lens at the rear of an optical device and nearest the user's eye.
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-and-under (O/U) ... Firearms (often shotguns, especially those used for clay-pigeon shooting) with two barrels placed one above the other, as distinct from side-by-side (see below).
Over bore capacity ... Common term used to describe cartridges with a propellant capacity overly large in relation to the bore. Expanding gas produced by propellant combustion can only be forced through a given aperture at a certain rate. Thereafter increasing the amount of gas by increasing the amount of propellant merely raises pressures without raising velocity. For example a .300 H&H case necked down to .22 calibre has twice the powder capacity of a .22-250 and produces maximum pressures that are much higher, but without noticeably higher velocities.
Over-pressure ... The rise in local air pressure caused by the firing of a gun, something that is especially noticeable with the muzzle blast from a black powder pistol which can often be felt by the shooter and bystanders.
Over-travel ... The amount of rearward travel of the trigger after the release of the sear.
Palm Rest ... 1) A height adjustable support for the non-firing hand of the user of a target rifle, extending downward from the forearm of the stock. 2) A height adjustable rest at the base of the grip of a handgun.
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 without parallax adjustment, as these sights will only be free of error at one distance, which is usually 100 yards. Note that this is not the same thing as focussing and if a telescopic sight does not have an adjuster ring near the object lens, then almost certainly it does not have parallax adjustment. This means that apart from the one distance at which it is parallax free (usually 100 yards) it will be of little value for accurate target shooting purposes, no matter with what gun or ammunition it is used.
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 barrelled gun, usually under 24 inches long overall and held in one or both hands without any other support. 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 a 10 shot Olympic Final, where scoring is done in 1/10 points, the maximum is 109.
Primer ... a) An explosive compound fitted either all around the rim of a rimfire cartridge case, or in a centrally mounted cap (usually replaceable) for centrefire 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 Flintlock gun.
Primer Pocket ... The recess in the base of the cartridge case that accepts the primer. In military ammunition it is usually crimped and sealed with a red coloured lacquer sealant for water-proofing.
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 ... Prone shooting is mostly for rifle and is done lying face down, supporting the upper body on the elbows. The rifle is held by both hands and often braced by a sling, which attaches to the fore end of the gun at one end and the shooters upper arm by means of a cuff at the other. Pistol can be shot prone, but it is an uncomfortable experience involving considerable neck strain and requires the use of both hands.
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.
Propellant ... 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 within the UK.
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 both before and after firing 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 by the Army following a formal inspection of the premises.
Rate Of Twist
... The length over which the rifling grooves in a barrel make one complete
revolution of 360 degrees. For example, a rate of 1:10 equates to one revolution
in 10 inches. The required rate differs from calibre to calibre and in general
is more rapid for small diameters than for large. Bullet weight must be
appropriate to the rate of twist or bullets will not be stabilised in flight.
The heavier and therefore the longer the bullet for any given calibre, the
faster the rate of twist must be. See Greenhill's formula above.
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.
Regulate / Barrel Regulation
... In double-barrel rifles, the process of getting
both barrels to shoot to the same point of impact with a given load at a given
distance. This distance is normally
set to the range for which the gun is intended to be
used and for big game rifles it is often quite short (under 100 yards).
The further away from this regulated distance one shoots, the more one must
compensate for left/right point of impact, also it is normal
for the manufacturer to specify which barrel should be fired first for best
accuracy. The points of impact for the two barrels are
usually quite badly affected by heating and so these guns are not intended for
sustained rates of fire.
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.
Retina
... The light sensitive
layer of cells at the back of the eye. It consists of
two main types of cell, rods, for
mainly black & white sensitive vision and cones
for colour sensitive vision. The
point where the optic nerve connects to the retina is bereft of light sensitive cells and is
known as, 'the blind spot'.
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 from bored-through
cylinders.
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'.
Rim ... On a cartridge case, the lip or flange around the case head, which provides purchase for the extractor claw. Initially all cases had projecting rims, i.e. rims larger in diameter than the case body, for example the .303 cartridge (today these cases are known as "rimmed" or "flanged" cases). The next type of case to be developed was the so-called "rimless" and in this instance the rim is of the same diameter as the body of the case, for example the 7.62 cartridge. There are a small group of cartridges with "rebated rim" cases, where the rim is smaller than the diameter of the case, for example the .284 Winchester.
Rimfire or Rim-Fire or Rim Fire ... 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 Long Rifle cartridge 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 this 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.
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 inches x 2.
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.
Semolina ... The inner, granular, starchy endosperm of hard or durum wheat, used as a filler material for black powder guns, it is more or less inert and being readily bio-degradable is very suitable for use on outdoor ranges.
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.
Side-by-side
... A double-barrelled
gun, the barrels of which are
horizontally aligned, one beside the other, as distinct from an,
over-and-under. This is the
traditional arrangement for shotguns and big game rifles.
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. 3) Note that some sights, especially those of German make, use the system whereby if the shots are going to the left, then turning the adjuster in the direction marked "L" will move the point of impact to the right: this needs to be thoroughly understood if disaster is to be avoided, especially under competition pressure! 4) In German, "L" stands for "Links", which means "Left". "R" stands for "Recht", which means "Right". "H" stands for "Hoch", which means "High" and "T" stands for "Tief", which means "Low".
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).
Six Shooter ... The name given to any six shot revolver, especially those associated with the Wild West of America.
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.
Smallarm(s) ... A military term used to mean any gun designed to be held in the hand when fired.
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 (gunpowder) 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 hand-held gun that is a smoothbore is a shotgun. Some military large calibre guns are smoothbores, but they use fin-stabilised projectiles to ensure good accuracy.
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.
Standing ... Shooting from the unraced standing position is the most difficult of all, as it is the most unstable of all the positions. Training can help a great deal, but nothing can remove all the wobble experienced by the marksman. A rifle is held in both hands and a pistol can be held in either one, or two hands depending on competition rules, or shooter preference.
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 and relatively expensive equipment involved.
Swarfega ... This is a propriety hand-cleaner much used in the past within the UK to seal the open ends of revolver chambers, so as to prevent a chain-fire taking place. Not much used today due to the mess it makes on indoor ranges: see Grease and Felt Wads above for more detail.
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 reaction ... 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 due to their greater bulk and increased support, but the phenomena still exists to some extent in all rifled weapons.
Trajectory ... See bullet path above.
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 (but may be pneumatic) 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 (revolution).
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 (feet per second): 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. Wheel Lock guns were expensive to make and relatively difficult to keep in good working order; as a consequence many were converted to Flintlock operation.
Wildcat ... A cartridge designed and made by a handloader by altering an existing cartridge case and usually displaying enhanced velocity over the original donor cartridge.
Windage ... The lateral sight adjustment so as to move the point of impact sideways on the target, this is usually, but not always done by the rear sight.
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.
Yaw
... The motion of a
bullet in flight spinning erratically around its own
axis, this is mostly due to air pressure on the nose of the
rotating projectile.
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 unsupported standing position, 10x for prone shooting and anything up to 30x and above, for bench-rest shooting.
Revised: 20-Apr-2022.