Media Info
    News releases
    Fact sheets
    Interview us
    Myths & truth
    Gun dictionary    
    Scary words
    SEA Effects
    FAQ

Photos & Videos
Training
News Coverage
General Info
Directions
History
Explosive Experiments
Bomb Help (NOT!)
Contact
Links

Home
Shirts, hats, stuff
Join News List
Privacy Policy

Reloading Supplies
Reloading Data

Gun Dictionary

Action*

Breech mechanism by which the gun is loaded, fired, and unloaded.  Action also contains either extractor or ejector that removes the empty shell casing once a gun has been fired.

ACP (as in .45 ACP, .380 ACP, and .25 ACP)

Automatic Colt Pistol.  A designation given to several different cartridges designed for use in a semiautomatic pistol and some fully automatic machine pistols.

Ammo, Ammunition

Ammunition is the consumable component of firearms system.  Ammunition is required to fire a gun.  A single unit of ammunition in modern firearms is called a cartridge.  The units of measure for quantity of ammunition is rounds.  There are hundreds of sizes of ammunition, examples include .223 Remington, 9mm Luger, 30.06, .308 Winchester, .300 Winchester Magnum, and .50 Browning Machine Gun (BMG).  The ammunition used must match the firearm.

ANFO

A mixture of Ammonium Nitrate and Fuel Oil.  This is considered a Blasting Agent by the ATF.  It is a cheap explosive but requires substantial heat and/or impact to detonate.  Usually dynamite or some other explosive is used as a booster make it detonate.  The Boomershoot explosive is a variation of this -- it uses potassium chlorate to sensitize the ANFO making the entire mixture easy enough to detonate with a supersonic bullet.

Arsenal

A name given to a collection firearms, ammo, and accessories by those who wish to demonize the owner of the collection.  Typically this is the term used by the media as they took pictures after the police piled a gun owners collection on the front lawn.  Under some proposed laws an arsenal was defined as a more than a certain number of firearms or cartridges and/or cartridge components such as bullets, powders, or primers.  The numbers specified were typically so low that you could become a "walking arsenal" by spending less than $15.00 and putting the contents of your purchase in coat pocket.

Autoloader

A firearm that automatically loads the next cartridge to be fired into the chamber either upon the pull of the trigger in an open bolt design or upon the firing of the previous round in a close bolt design.  Over time this term has been shortened to just "auto" and sometimes "automatic" thus creating confusion between a full-auto firearm and a semi-automatic firearm.

Automatic

An fully automatic firearm is capable of sequentially firing two or more cartridges with a single pull of the trigger.  A fully automatic firearm is also called a machine gun. 

Automatic can also refer to a semi-automatic firearm--see Autoloader.

Ball

See Full Metal Jacket.

Ballistic Fingerprint

1) The mistaken belief that a firearm marks the bullets and shell casings fired in it with unique markings that do not change over time and are not trivial to change by someone with a piece of sandpaper and a tube of toothpaste.  2) A means of registering all firearms for later confiscation.

Barrel

A narrow hollow cylinder portion of a firearm through which the bullet travels during the acceleration phase of it's journey to the target.

Bipod

A two legged support for the front end of a rifle to stabilize the gun while shooting.

Boat Tail

A type of projectile  that has a tapered base (rear end) that reduces the drag from the air as it travels to its target.

Bolt

The mechanism of some firearms that holds the cartridge in place during the firing process.  See also Bolt Action.

Bolt Action

A type of firearm, almost always a rifle, in which an empty shell casing (remnant of a cartridge) is removed from the firing chamber by the turning and retraction of a metal cylinder shaped mechanism called a bolt.  A new, unfired, cartridge is inserted and secured into the chamber by reversing the action of the bolt.  Bolt action firearms are typically the most accurate and are the most common type of firearm at the Boomershoot.

Boomer

1) Specific to the Boomershoot -- a reactive target made of high explosives.  2) Specific to the gun community -- a very high power rifle that makes a louder than normal noise.  Sometimes magnum rifles in general will be referred to as boomers. 3) A person born during the "Baby Boom" period following the conclusion of WWII.

We only shoot the Boomers fitting the first two definitions at the Boomershoot.

Bore

1) The hollow portion of a barrel through which the bullet travels during it's acceleration phase. 2) Someone not interested in talking about guns and/or explosives.

Bullet

A generally cylindrical shaped projectile that travels through the air after being fired from a firearm.  This is only one component of a cartridge, which is a single piece of ammunition.

Bull Barrel

A barrel which has the same outside diameter it's entire length. This type of barrel has the advantage of being very stiff and hence a greater potential to be accurate.  It has the disadvantage of being heavy.  Many of the rifles shot at the Boomershoot will have bull (or very slight taper) barrels.

Butt (of a stock)

The stock of a rifle or shotgun is usually placed against the shoulder to fire. The contact point with the shoulder is the butt of the gun.

Brass

1) A slang term for an empty shell casing.  Most shell casings are made of the metal alloy known as brass.  2) The personality trait that someone must have to believe they have the authority and/or power to remove 200 million firearms and billions of rounds of ammunition from 80 million people in the United States who believe the right to keep and bear arms is an individual inalienable right guaranteed by the Second Amendment to the Constitution. 

Can

Slang term for a firearm sound suppressor.

Carbine*

A short, lightweight rifle with a barrel that usually measures less than 22". In German, Karabiner means carbine.

Cartridge

The assembly of a bullet, shell casing, gunpowder, and primer that is put in the chamber of a firearm.

Caliber

1) The diameter of the bore of a firearm.  Typically in millimeters or a decimal fraction of an inch.  2) Common usage, but imprecise -- the name of the cartridge used in a firearm.  Examples include .223 Remington, 220 Swift, 22-250 which all use the same bullet, but different cartridge, because they have the same diameter of bore.  Other examples include 7.62 NATO, .308 Winchester (same as 7.62 NATO), 30.06,  and .300 Winchester Magnum.  Again these all used the same bullet but a different cartridge.

Cap

See Percussion Cap.

Case

See Shell Casing.

Chamber

The portion of a barrel where a cartridge is placed just prior to being fired.  This is a high pressure containment area which is very precisely aligned with the bore of the barrel.  A gun cannot be fired when the chamber is empty.  At the Boomershoot guns must have the chamber visibly open when not on the firing line or when people are down range.

Charge

See Powder Charge.

Clicks

A unit of adjustment for a sight.  Typically equal to one quarter of one MOA, but may range from one eighth to one half of one MOA.

Clip

A device that holds cartridges in place prior to be put into a magazine of a firearm.  Hollywood, the media in general, and even a lot of shooters get this wrong.  A clip is not the same as a magazine. 

Centerfire Cartridge

A cartridge that has a primer located in the center of the base of the shell casing.  This is as opposed to a rimfire cartridge.

Cock, Full

See Cocked.

Cock, Half*

A notch in the sear and hammer that forestalls accidental hammer fall, which would fire the gun.  When on half cock, the hammer is disengaged from the trigger mechanism, hence the gun is safe while the hammer is in this position.  In some revolvers, placing the hammer in the half cock position allows rotating the cylinder for loading or unloading.

Cocked

A state of readiness of a firearm.  The hammer (or similar mechanism if there is no hammer) only needs to be released by the trigger to cause the gun to fire.

Cold clean bore

The first shot from a rifle that has been cleaned, and not fired recently may go to a different point of impact, for the same point of aim than a rifle that has been fired recently.  This first shot is referred to as a shot from a cold, clean, bore.  See also fouling shot.

COM

Center Of Mass.  For combat or self-defensive shooters, COM represents the area of an assailant's torso within which the most vital organs are likely to be disrupted by a gunshot. Shooting to COM is considered the most expedient way to stop an assailant from continuing threatening behavior.

Comb

The top part of the stock, ahead of the butt, where the shooter rests his cheek is called the comb.

Compound

A term used by law enforcement and the media to demonize a firearms owner when referring to his home.  Typically this is when their home is in a somewhat rural area and has one or more outbuildings.  Some of the more famous examples include the homes of the Branch Davidians, Randy Weaver and the Montana Freeman.

Confiscation

A means of disarming future victims.  Victims and confiscators come in two types: A) Victims of tyrannical governments such the Jews in Nazi Germany.  The Nazi's Weapons Control Act of 1938 forbid Jews to posses firearms and was the basis for the United States Gun Control Act of 1968 (see the website for Jews for the Preservation of Firearm Ownership for more details); or B) The common person who has their means of self defense removed by misguided, well intentioned, fools in places like England where violent crime has skyrocketed since firearms in particular and self-defense in general has been banned. 

Cylinder*

A rotating cartridge container in a revolver.  The cartridges are held in the chambers and the cylinder turns, either to the left or to the right depending on the gun maker's design, as the hammer is cocked.

Double*

A two barrel gun where the barrels are aligned side-by-side.  Although over/under shotguns are actually also double guns, usage limits the term to side-by-side guns.  Double guns are usually smooth bored, but double rifles, for dangerous game, are sometimes encountered in the U.S.; are fairly common in England, Europe, Africa, as well as in India.

Down Range

The area of a gun range where firearms are pointed when they are fired.  The area of the range forward of the firing line.

Dot Sight

An optical device used for aiming a firearm, usually consisting of an illuminated dot or other simple reticle, superimposed in a non-magnified field of view by a hologram or through prisms or mirrors. The reticle is generally powered by small batteries, a radioactive isotope (tritium), or a light-gathering fiber optic. Although dot-sights typically have low magnification (maximum 1.5x), they are extremely fast for target acquisition and do not suffer from parallax.  They may also be called a "Red-Dot" sight because the dot is typically red in color.

Ears

Slang for ear protection.  A set of specially designed ear muffs or plugs that reduce the intensity of the sound reaching the ears.  Some of the guns are so loud that a single shot can can cause permanent damage to unprotected ears.  Because of the high tax and restrictions on firearm sound suppressors very few people in the US shoot firearms with suppressors.  In some European countries it's considered impolite to shoot a firearm without a sound suppressor.  At the Boomershoot ear protection is required for shooters, spotters and nearby spectators while shooting is in progress.

Ejector*

A spring-activated mechanism for the ejection of ammunition or and empty shell casing.  On doubles, each barrel has a separate ejector.

Elevation

1) The setting on the sights of a firearm that controls the vertical placement.  2) The altitude above mean sea level.  This is important for long range precision shooting because the air density changes with elevation and affects the path of the bullet.

Extractor*

A device that withdraws or elevates a fired shell casing or a live round from the chamber as the breech mechanism is opened.  See also ejector.

Eyes

Slang for safety glasses or other protection for the eyes.  Although very rare, firearm accidents do happen.  The biggest danger at the Boomershoot is flying brass (cartridge shell casings) which carries a very low risk of serious injury.  In the case of a serious accident such as an accidental discharge into the nearby ground or a catastrophic structural failure of a firearm during the firing process there may be high speed dirt or metal particles flying around.  These could result in serious eye injury if safety glasses are not used.  All shooters and spotters are required to wear eye protection while shooting is in progress.

Factory Ammo

Ammunition that has been assembled by a commercial vendor of ammunition and sold in retail stores.  This is as opposed to Handloads which have been assembled by individuals and are not typically sold.  

Firearm

A gun which uses the combustion of some chemical mix, typically smokeless gunpowder,  to propel a projectile.  Firearms are typically divided into long guns and handguns.   

Firing Line

A line, either imaginary or marked, from which people shoot their firearms down range.

Firing Pin

A needle like metal part of a modern firearm that gives a vigorous strike to the primer initiating the firing of the cartridge. 

Flash Hider

See Flash Suppressor.

Flash Suppressor

A device affixed to the muzzle of a firearm barrel, designed to minimize the bright flash caused by escaping hot gases and burning powder residue upon firing.  Also known as a Flash Hider.

Forend*

That part of the stock forward of the action and located below the barrel or barrels.

Fouling Shot

A shot fired in a clean rifle barrel to put the barrel into the normal slightly dirty state from which it is fired.  Often, a rifle will shoot to a different point of aim with this shot as compared to the subsequent shots.  See also, cold clean bore.

Full Metal Jacket

A type of bullet in which the lead core is encased in a copper jacket on the front and sides.  The copper jacket may also include the base, but this is more rare.  This type of bullet is relatively cheap and used for target practice or by the military.  Sometimes called "Ball" ammo.

Grains

A unit of weight (mass actually) used for measuring bullets and gunpowder.  There are exactly 7000 grains in one pound.  Typical .30 caliber bullets range from 125 to 220 grains.  .22 caliber bullets for centerfire cartridges range from about 50 grains to 70 grains.  Typical weights of gunpowder used in one cartridge range from about 20 grains to 80 grains depending on the cartridge type, powder type, bullet weight, and desired muzzle velocity.

Grooves

The portion of the bore in a rifled barrel (see rifling) that has been machined away. The diameter from the depth of one groove to its mate across the bore axis forms the widest diameter of the bore.  See also Lands.

Group*

A number of shots fired at a given range at one target & with one sight setting, with either rifle or handgun, to determine the accuracy of either the gun or the ammunition. 

With a handgun the most common range is probably 25 yards.  A two inch group is generally considered good.  With a rifle it is probably 100 yards with a one to two inch group being considered good.  The number of shots in a group affects the size and when comparing the size of groups achieved with one firearm to another the number of shots must be taken into account.

The group size is measured by finding the bullet holes that are the furthest apart from each other and measuring from the center of one hole to the center of the other hole.  Obviously the number of shots fired affect the group size.  Typical numbers are three, five and ten.  From a statistics viewpoint a three shot group is virtually meaningless as a measurement of firearm accuracy.  Five shot groups are acceptable. Some advocate a seven shot group as a good tradeoff between economy and statistical relevance.

Gun Control

1) Being able to hit your target. 2) A political tool to disarm victims.

Gunpowder

A chemical mixture or compound that burns rapidly with or without the presence of air to produce hot pressurized gases capable of propelling a bullet.  There are two basic types of gunpowder, Black Powder and Smokeless Powder.  Black Powder is composed of a mixture of charcoal, sulfur, and potassium nitrate and produces a cloud of white noxious smoke when it burns.  Smokeless powder burns much cleaner but may still produce a small puff of smoke.  All modern firearms use smokeless powder, not only because there is less smoke, but because the bullets can be made to exit the gun faster.  There are some people that love the challenge of shooting a black powder type firearm and organizations exist that cater to that group of people.

Hammer

Similar in function to the carpenter and mechanics tool the hammer of a firearm is propelled by a spring to strike either directly or via a firing pin the primer of a cartridge causing the gun to fire.

Handgun

Handguns are designed to be fired from outstretched arms and include pistols and revolvers.  It is rare that a handgun will be used at the Boomershoot.

Handloads

Handloads are cartridges assembled by an individual person from the individual components (primer, shell casing, gunpowder, and bullet) and are typically tailored specifically for their firearm.  Handloads are usually cheaper than purchasing factory ammo.  Probably about half of the shooters at the Boomershoot will be shooting handloads.

Heel (of a stock)

The top of the butt, when the gun is in position on the shoulder to be fired, is called the heel. 

High Power

A high power rifle uses a centerfire cartridge.  The alternative is a rimfire cartridge such as a .22 Long Rifle.

Hollow Point

A type of bullet that has a hollow point at the front end.  In a pistol it would be used for self-defense because the bullet expands upon contact with the target producing a greater wound cavity. It is also less likely to over-penetrate, pass through the attacker, and hit an innocent person on the other side.  In a rifle hollow point bullets are typically used for high precision shooting because during the manufacturing process the base can be made much more symmetric which is critical for an accurate bullet.  Minor irregularities of the hollow point are much less critical than similar irregularities in the base.

Iron Sights

Sights made of metal with no optics.

Junk Gun

Used in reference to inexpensive handguns, “junk guns” is not only a deceptive term, it is also elitist. Affordable guns are an accessible means of self-defense for those with low incomes, especially people who live in poor, unsafe neighborhoods. Please note that politicians commonly talk about banning “junk guns” yet they themselves are typically afforded the luxury of armed guards. Again, it is elitist. See also Saturday Night Special.

Kick

Slang term for recoil.

Lands

The portion of the bore in a rifled barrel (see rifling) that protrudes into the bore itself. The top surface of the lands is approximately the same diameter as the bore was prior to rifling.  See also Grooves.

Long gun

Long guns are designed to be fired while in contact with the shoulder of the shooter and include rifles and shotguns.  There have not been any shotguns used at the Boomershoot.

Lever Action

A type of gun that uses a lever operated mechanism to remove an empty shell casing and insert a new cartridge in the chamber of a rifle.  Other types of mechanisms include bolt action and pump action.  Only one lever action rifle has been used at the Boomershoot.

Magazine

1) A ammunition feeding device that holds the cartridges just prior to them being put in the chamber of the firearm by the operation of a mechanism on the firearm.  This mechanism may be operated manually as in a bolt action or semi-automatically when the gun fires after pulling the trigger.  The magazine may be detachable or part of the gun (as in a tubular magazine common with lever action rifles and most semi-auto and pump shotguns).  The detachable ones are what Hollywood, the media in general, and many shooters refer to as a clip.  This is wrong.  A clip is different from a magazine.  2) A storage area for explosives.  The Boomershoot range has an ATF approved and inspected explosives magazine for the reactive targets.  It is bullet and theft resistant.  See pictures and find out more about it by clicking here.  3) A periodical such as Precision Shooting.

Magnum

A cartridge that has more powder and shoots the same weight bullet faster than some previous similar cartridge.  As much a marketing term as a technical description.  Familiar magnum cartridges include .357 Magnum, .44 Magnum, and .300 Winchester Magnum.

Match Grade

A higher quality item used to increase accuracy -- generally used for competition in a match.  Match grade ammo and barrels are the most common improvements made to a firearm to improve accuracy for competition.

MOA

See Minute Of Angle.

Mil-Dot

A type of 'viewfinder' in a telescopic sight that has dots spaced one mill radian (a unit of angle related to degrees -- as in 360 degrees in a circle).  There are 2000 times Pi or 6283.2 milliradians in a complete circle.  This spacing of dots lends itself to relatively easy measuring of range to the target under many circumstances.

Minute Of Angle

Also called MOA.  A unit of angle that is equal to one1/60 of one degree.  Used to adjust sight angles to aim a firearm.  At 100 yards one MOA is equal to very nearly 1 inch.  Typical telescopic sights used for competition have adjustments (clicks) in one quarter MOA increments.  In most situations a rifle must be able to shoot one minute of angle or less sized groups to be considered highly accurate.

Slang usage: "minute of pop can", "minute of deer", "minute of barn", or some other type of target.  This implies a level of accuracy necessary to hit that particular target under "normal" conditions.  It can be an approving comment as in "It's good enough for minute of deer."  Or derogatory, as in "That gun can't shoot minute of barn."

MSGC

Microsoft Gun Club.  The event director worked for Microsoft and was a member of the Microsoft Gun Club at the time of his first successful Boomer experiment.  A month later the first Boomershoot occurred with most of the participants being fellow MSGC members.  See also the report posted to the MSGC email list.  The MSGC is still well represented at this annual event.

Muzzle

The end of the barrel where the bullet exits as it is being fired.

Muzzle Brake

An attachment to the end of a barrel that redirects some of the pressurized, gas that propelled the bullet out the muzzle to the sides and possibly rearwards from the direction of the bullet travel.  This reduces the recoil of the firearm.

Muzzle Velocity

The speed of the bullet as it leave the muzzle of the gun.  Typically this is measured in feet per second.  For handguns typical velocities range from about 800 feet per second to about 1400 fps.  For centerfire rifles the range is from about 2200 fps to 4000 fps.

Nipple*

1) On percussion guns, the nipple is a small, threaded tube on which the percussion cap is placed.  The nipple connects with the chamber so that when the cap is exploded by the hammer the flash of the cap travels through the nipple into the chamber igniting the powder charge there.  2) Don't worry, I'm not going there.

Overbore Capacity*

Overbore capacity is that combination of caliber, barrel length, bullet weight, and case volume which does not allow the complete burning of the charge of ballistically correct powder within the volume of case and barrel.

Parallax

This occurs in telescopic sights when the primary image of the objective lens does not coincide with the reticle.  In practice, parallax is detected in a scope when, as the viewing eye is moved laterally, the image and the reticle appear to move in relation to each other.  Telescopic sights often have parallax adjustments to minimize this effect. Dot sights typically do not suffer from this effect.

Percussion Arm*

Any type of gun fired by the percussion system.  In this ignition system the powder charge was ignited by a percussion cap, the fore-runner of the modern primer.  The cap was placed on the nipple and when the hammer hit the cap, the flash of the detonating charge in the cap traveled through the hollow nipple, thus igniting the charge in the barrel.  Black powder shooters of today often use replica percussion arms in competitive shooting events.

Percussion Cap*

The small cap that contains a detonating charge of fulminate.  See also Percussion Arm.

Projectile

An object given an initial velocity which proceeds on it's one inertia through the air and perhaps solid objects in it's path.  A bullet fired from a gun is a projectile.

Pistol

A handgun whose chamber is integral with the barrel.  This is opposed to a revolver.

Pistol Grip

1) A section of a rifle stock shaped like the grip of a pistol.  2) A variation of stock type that is so offensive to some legislators they have seen fit to place restrictions on it.

Powder

See gunpowder.

Powder Charge*

The amount of propellant powder that is suitable for specific cartridge-bullet combination, or in the case of shotshells, for a specific weight of shot and wad column.  In handloading, powder charges are either weighted on accurate scales, or are thrown by a powder measure which works on the volumetric system.

Primer

A small metal cup that contains a tiny explosive charge that is sensitive to impact.  A primer is placed in the base of a shell casing to ignite the powder of the completed cartridge.  It is detonated by the striking of a firing pin in the firearm.

Pump or Pump Action

A type of mechanism for removing a spent shell casing from the chamber of a firearm and inserting a fresh cartridge into the chamber.  This type of mechanism is most commonly used in shotguns and rimfire rifles.  There have not been any pump action firearms used at the Boomershoot.

Range Finder

A device used to determine the range to a target.  Range finders of recent manufacture used by Boomershooters work by bouncing a laser beam off the target or nearby object and measuring the time for the reflection to arrive back at the instrument.  It is also possible to use various passive optical devices such as a mil-dot telescopic sight.

Registration

1) A method by which a gunsmith makes all the slots of the screws in a firearm line up.  Usually this involves such things as machining a new slot in the screw.  This is usually done only in very high quality firearms intended for display.  2) A subterfuge sold to the public as a means of catching criminals.  Even though researchers have not been able to identify any criminals having been caught because they were stupid enough to have used a firearm that was registered to them and then left it at or near the crime scene.

Receiver

The portion of a rifle that has the serial number on it.  The stock, barrel, and other components such as the bolt are typically attached to the receiver.  Some firearms may have a multipart receiver such as an upper receiver and a lower receiver.

Recoil

The sudden rearward push made against the shooter when a firearm is fired.  This push is due to Newton's Third Law of physics (for every action there is an equal and opposite reaction). The heavier the bullet and the faster it leaves the muzzle of the barrel the more recoil.  The weight of the powder and the velocity of the gases it produces at the muzzle also enters into the equation describing the total recoil.  These high velocity gases are what enable a muzzle brake to reduce the recoil without reducing the velocity of the bullet.

Red-Dot

See Dot Sight.  Also a brand of smokeless gunpowder.

Regulate (as in regulation of barrel convergence)

Double barreled guns need to be adjusted so both barrels shoot to the same point of aim at some particular distance.  Typically this would be something like 50 or 100 yards.  This is dependent on the ammunition used as the weight and velocity of the bullet as it traverses the barrel changes the position of the gun.

Regulate (as in a well regulated militia)

From The New Century Dictionary, copyright 1936: Adjust so as to ensure accuracy of operation (as, to regulate a clock or a watch); in general to put in good order (as, to regulate the digestion).

From w-m.com: To bring order, method, or uniformity to (regulate one's habits).

Reticle*

Also erroneously called reticule, the sighting device in a telescopic sight or scope.  The reticle, which may consist of various arrangements of crosshairs, post or dot, is adjusted so that it appears to be on the same plane as the target.   If the adjustment is off then parallax can occur.

Revolver

A type of handgun which has multiple chambers which each revolve into position to fire a cartridge.  Six chambers in a revolver are common, but five, seven, and nine are not unusual.

Rifle

A firearm designed to be fired from the shoulder and fire only a single projectile at a time, as opposed to a shotgun which can throw many small projectiles (shot) at the same time.

Rifling

An arrangement of helical grooves machined into a barrel to impart a spin onto a projectile passing through the bore. The spin stabilizes the projectile, providing better range and accuracy. Rifling may be cut into a barrel through the use of various cutting tools or broaches, may be pressed into the barrel using a button tool to displace metal, or may be formed by hammer forging the barrel around a mandrel that contains a reverse image of the final rifling pattern.

Rimfire Cartridge

A type of cartridge whose primer is integral to the shell casing and located along the edge of the base in a rim.  When the firing pin strikes it pinches the rim against the chamber and causes it to detonate and ignite the powder. 

Rounds

A unit of measure for ammunition.  One cartridge.  Typical quantities are 20 rounds and 50 rounds in single box.  A Boomershooter will typically go through about 100 rounds in one day.  At some pistol matches a shooter may go through several hundred rounds.  In a weekend of training, a pistol shooter may go through 1500 or more rounds. 

Safety (mechanical)

A mechanical device used to block the firing pin or trigger such that the firearm cannot be fired.

Safety Rules

Rules that must be followed to insure the safety of people and property.  The minimum safety rules taught by the NRA and enforced at the Boomershoot are:

1) Always keep the gun pointed in a safe direction.
2) Always keep your finger off the trigger until ready to shoot.
3) Always keep the gun unloaded until ready to use.

Saturday Night Special

Anti-gun slang for an inexpensive handgun. A deceptive, elitist, and racist term, the so-called "Saturday night specials" are small, inexpensive, low-caliber handguns, commonly used by poor people for self-defense. Gun confiscators typically associate this term with criminals. However, from a commonsense perspective, if a criminal were a criminal, s/he’d despise this type of gun (logically assuming they’d prefer a more powerful gun to fight the police).

As for the history of the term, "Saturday night special", David Kopel, Research Director at the Independence Institute, explains:

[The] “Saturday night special” is in part a linguistic descendant of the racist phrase "Niggertown Saturday Night." The obvious implication of the phrase "Saturday night special" is that it is a gun used by "niggers" to shoot each other with during their wild Saturday nights. No one denies that the people disarmed by a "Saturday night special" ban would be predominantly poor and non-white.

Again, as with “junk guns”, affordable guns are an accessible means of self-defense for those with low incomes, especially people who live in poor, unsafe neighborhoods. Politicians commonly talk about banning these cheap guns, yet they themselves are typically afforded the luxury of armed guards. The term “Saturday night special” is elitist and racist. See also Junk Gun.

Click here for more history on the racist roots of gun control.

Scope

See Telescopic Sight.

Semi-Auto

A firearm that uses the energy and momentum of the just fired cartridge to eject the spent shell casing and load a new cartridge into the chamber.  This makes it an automatic loader.  This is sometimes shortened to 'automatic' which some people confuse with a full-auto (machine gun).  This is the second most common type of firearm used at the Boomershoot -- a distant second with bolt actions being far more common.

Shot*

Shotgun

A (typically) smooth bore long gun that shoots a group of pellets called shot instead of bullets.  Depending on the bore size and the size of the pellets there may be from less than 10 to two hundred or more pellets in a single shotgun cartridge.  Shotguns are designed for shooting moving targets (such as flying birds or running rabbits) at close range and are not used at the Boomershoot.

Shotshell*

A self-contained round of ammunition consisting of a case of brass head, a primer, a powder charge, wads, and a load of shot, being close by means of a crimp.  Early shotshell cases were made of brass and were reloaded many times by the shooter.  Paper hulls with a brass head replaced the brass cases and the paper hulls have now been replaced by plastic hulls with brass heads. 

Shell Casing

A hollow, bottle or drinking glass shaped, piece of metal that is closed on one end except for a small hole which holds a primer.  The open end holds the bullet.  The hollow portion holds the powder.  Together the assembled unit is called a cartridge. 

Sights

The device that aids the eye in aiming the barrel of a firearm in the proper direction to hit a target.  The most common sights are iron and telescopic.  Nearly all Boomershooters use telescopic sights.

Soft Point

A bullet that has an exposed lead tip.  These type of bullets are typically used for hunting game animals with a rifle because they expand to create a larger wound channel than a full metal jacket bullet.  A hollow point bullet would be used with a handgun for the same reason.  A hollow point bullet fired from a rifle frequently fragments upon impact and fails to penetrate deep enough to cause a humane kill in game animals.  A hollow point varmint bullet is often used when hunting small animals not intended to be used for food or fur.  

Spotter

The spotter is a helper who gives the shooter guidance on how to hit a particular target.  In some cases the spotter may just report the location of the bullet impact.  In other cases they may judge the speed and direction of the wind, determine the range, and give the shooter the settings to be used on the sights.  If the atmospheric conditions are good and he/she is using quality optics the spotter may even see the bullet as it travels through the air towards its' target. With the right optics trace can also be seen under most shooting conditions.

Stock

The supporting structure of a long gun to which the receiver, barrel, trigger, and other components are attached.  Typically this is the portion of the firearm the shooter holds while firing it.  See also toe, heel, butt, and comb.

Telescopic Sight

A sight which has an integral telescope.  Most guns used at the Boomershoot will be of this type.

Toe (of a stock)

The bottom of the butt, when the gun is in position on the shoulder to be fired, is called the toe.

Trace

Visible disturbance in the air by a bullet. Typically this takes the form of image distortion that persists for a fraction of a second in the shape of an inverted V similar to that of a boat wake.

Trajectory

The path which a bullet takes from the muzzle of the barrel to it's initial point of rest.  A bullet in flight does not fly straight to its target. In fact, the bullet begins dropping under the influence of gravity as soon as it leaves the barrel. To compensate for this, the firearm's sights are aligned to point the barrel upward and perhaps to one side or the other to compensate for the wind.  This causes the bullet to arc upward relative to the line of sight within the sighting system, then downward under the influence of gravity to its point of impact. The sights are adjusted in elevation and windage to change it's angle with the barrel to make the bullet point of impact coincide with the point of aim.  Sophisticated computer programs, such as Modern Ballistics, are used to predict the path of various bullets fired at various velocities under various conditions.

Trigger

The mechanism used by the shooter to initiate the firing of a cartridge.  Typically this is a lever type piece of metal that must be pulled with the index finger.

Trigger Guard

A metal (or sometimes hard plastic) mechanical device which partially covers the trigger and reduces the chance the gun will be accidentally fired.

Trigger Lock

A locking device put on a firearm to render it unable to be fired.  This can be useful in a home which does not have a gun safe and has small children.  It can be a disaster when it is legislated as a "one size fits all" solution because it renders all home stored firearms useless for self-defense.

Unintended Consequences

1) The phenomena of (usually) adverse consequences resulting from (usually) well intentioned actions.  Gun restrictions and/or bans are prime examples.  The intent is (usually) to reduce crime.  The consequence is that the victims are disarmed more than the criminals with the result that violent crime increases.  2) A book by John Ross which has become a "cult classic" within the gun community. 

Varmint Bullet

A hollow point, thin jacketed, bullet that is designed to fragment into many (perhaps hundreds) of pieces upon impact.  This type of bullet is designed to humanely kill a small animal such as a prairie dog or ground squirrel.  Because they break up into so many pieces while still retaining high velocity a hit from one of these bullet will cause the animal to essentially explode even if hit a long way from a vital organ.  A full metal jacket bullet that hit in the same location would typically pass through the animal.  The animal would die minutes, hours, or perhaps even a day later from dehydration, infection, or from inability to escape from a predator.  Because varmints are typically hunted at long distances the bullet are typically made to be very accurate as well.

Wad*

1) A felt, paper, cardboard or plastic disk that is used in a shotshell.  Wad design and material varies with the intended use of the wad, the ultimate use of the shell, as well as the gauge.  2) Never mind, it's pornographic.

Wind Doping*

The ability to calculate wind deflection and compensate for its effect on a projectile.  Wind doping is a matter of experience and many good riflemen have the ability to dope wind to such an extent that computers are not required to get acceptable results.

Windage

The setting on the sights used to accommodate the wind or adjust for horizontal errors in the alignment of the sights with the bore of the firearm. 

* Entries marked with an asterisk are at least in part from The Firearms Dictionary by R.A. Steindler, copyright 1970, published by Stackpole Books.