McKinney Firearms Training, LLC

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Designation for ammo that is overloaded to make it slightly "hotter" (more powerful) than the standard for that caliber. Typically available for 9mm, .45 cal, and .38 Special. Not all guns are built to withstand the higher pressures, so check your owner's manual before using any +P.
NOTE: while some manufacturers sell .380 +P, there is no recognized standard for that caliber. Using it could damage the gun.


A generic term for a full-sized pistol with a shape similar to the iconic Browning Model 1911.

6 o'clock hold

For complicated reasons of physics and ballistics, a bullet does not travel in a completely straight line. At 10 yards or less, the difference is generally too small to measure, so this is more important for rifles than pistols, but even a pistol will display this error at 15 yards or more. A gun that shoots to POA (point of aim) at 7 yards may shoot several inches high at 25 yards. Most people don't shoot a pistol at 25 yards, but if you do, and this happens, aim below the target zone. If the target is round, like a bullseye, envision it like a clock, and aim at the bottom (6 o'clock). This is also called "pumpkin on a fencepost".

.357 Sig

A relatively uncommon caliber intended to graft the ballistics of the .357 Magnum revolver onto the autoloader platform. Think of it as a .40 caliber on steroids. It is becoming increasingly common as a police sidearm. It was developed by the Sig Sauer company.


Automatic Colt Pistol cartridge, an industry standard.


The Armalite Rifle, developed in the 1960s by the Armalite Corp to replace the aging M-1 combat rifle. It featured a shorter barrel, an adjustable stock, 20 round removable magazine, a built-in shock absorber, select-fire, an easier take-down process, and a smaller but faster bullet. It was labelled the M-16, and production was eventually taken over by Colt. The AR-15 is the civilian version of the M-16, and does not allow for select-fire. The AR is considered a "platform" rifle, in that, while they are manufactured by hundreds of companies, they all have identical operational controls, and similar features.

AR-15 Pistol

A very short version of the AR rifle above, but fitted with an arm brace so it can be fired one-handed. The presence of the arm brace, through which you slide your forearm, is a sham, as hardly anyone shoots these guns one-handed, especially when they are equipped with a red-dot, scope, or light. However, removing or disabling the arm brace makes the gun, legally, a short-barrelled rifle (SBR), and restricted under the terms of the National Firearms Act of 1934. Firing the gun by putting the short stock against your shoulder is not illegal, but removing or modifying the arm brace is. Don't you love loop-holes? [This is currently in litigation]

Assault Rifle

More properly called a "breaching rifle", this is a short, select-fire rifle, capable of both semi-auto fire and full-auto or burst mode (sub-machine gun). These are illegal for civilians to own, except for people (mostly collectors) with a high degree of trust from authorities, and include weapons like the American M-16 and M-4, the Israeli Uzi, and the German Hechler & Koch MP5. They cost thousands of dollars, and require as much as a year of Federal paperwork and background checks to acquire. The AR-15 and AK-47 are not breaching rifles, but standard semi-automatic rifles, similar in function (though not appearance) to common hunting and target rifles.


Another term for a semi-automatic pistol.


At a firing range, the obstacle behind the target that keeps the bullets from leaving the range and possibly causing damage or injury elsewhere. It can be a hill or high mound of earth backed up with concrete blocks, or a slanted concrete floor that guides bullets up into an overhead construction to minimize ricochets. Never try to shoot over the backstop, and be very wary of shooting anywhere without a suitable backstop. A stray bullet can travel hundreds of yards.


The rear part of the pistol grip, facing your palm. Some models have interchangeable backstraps, which can change the overall size of the grip to fit smaller or larger hands. When the grip is too big for your hand, there may be a tendency to address the trigger laterally, and cause shots to go left. When the grip is too small for the length of your fingers, you may put too much finger on the trigger, and pull right.


A sharp outward curve of the back of the grip just below the hammer or back of the slide. It fits into the soft fleshy part of the hand between thumb and index finger. It keeps you from getting your hand too high and getting caught by the mechanism. That said, your hand should be as high on the gun as possible, without trying to get above the beavertail.

Bolt Action

A rifle and shotgun mechanism whereby the breech is opened and closed by a manually operated bolt.


The interior of the barrel through which the charge of the bullet passes.


The point at which the trigger releases the hammer or striker.


The rear end of the barrel into which a cartridge is inserted.


The metal slug at the front of a cartridge; the only part that travels through the barrel and out of the muzzle.

Bullet Drop

The vertical drop of a bullet due to gravity. More significant for rifles than pistols.

Bullet Setback

Semiauto only. Users will sometimes unload a handgun (for cleaning or going to the range), take the cartridge from the chamber, and put it back into the magazine, on top. Subsequently, when reloading, that cartridge will be loaded into the chamber again. Constantly loading the same cartridge into the chamber over and over can cause the bullet to be pushed back into the casing a small amount (bullet setback). If that amount is too much, internal pressures could cause the cartridge to explode. Some users move those cartridges to the bottom of the magazine, then, every few months, replace the ammo in the carry mag.


The measurement of the bore of the barrel; used to describe both the pistol and the ammo it shoots, i.e., .40 cal = 4/10 inch. For historical reasons, some caliber designations are not technically correct: both .38 and .380 are not correct, for different reasons. We just have to live with it, like the fact that Columbus did not discover America.


Often confused with bullet, this is the entire cartridge that holds the bullet and powder.


The part of the cartridge that is left after the bullet is shot out of it. They are reusable, and used by people who reload their own ammo.


With the exception of the few rimfire calibers, most cartridges have the primer located in the center of the base of the casing. The firing pin has to strike the cartridge in the center to fire it.


The section at the rear of the barrel that is large enough for the cartridge. The cartridge is fired in the chamber, but stays there until removed, while the bullet travels down the barrel. An autoloader only has one chamber (which is emptied immediately on firing), while a revolver has 5-7 chambers in a rotating cylinder.


Acronym for Concealed Handgun License, known in some jurisdictions as CCW (Concealed Carry Weapon) or CWP (Concealed Weapon Permit). In Texas it is known as LTC.


The act of removing the magazine and extracting all cartridges from an autoloader, or removing all cartridges/casings from a revolver, thus making it obvious to a witness that the pistol is completely safe. One should always clear a pistol/rifle before stepping away from the firing line, before carrying the gun (cased or uncased) anywhere, or before handing it to someone.


Not a magazine. See moon clips and stripper clips.


Typically applies only to pistols. When the iron sights can also be viewed through an optical sight, they are said to "co-witness", so if the battery in the optical sight fails, you can still aim. This is very desireable, but not always the case. Sometimes the optical sight is too tall, or the rear sight may have to be removed entirely to install the optical sight..


The swinging unit which hinges the cylinder of a revolver with the frame.


In a revolver, the cylinder holds the 5 to 7 chambers (but usually 6), into which are inserted the cartridges.


When a pistol (that has an external hammer) is in single-action mode, the shooter should not stop for any significant amount of time without letting the hammer back down. Since most people do not know how to decock a pistol properly, some guns come with a decocking lever which will do this safely.

Double stack magazine

A wider than normal pistol magazine that allows cartridges to load in an overlapping fashion, with the result that the magazine holds more ammo than its height would suggest. The pistol grip has to be wider to accept it. Sometimes these pistols are harder to conceal, due to the added width. Many people think that is a good trade-off, since it carries more ammo than a similar single stack magazine.


The trigger performs two actions: cocking the hammer against a spring, and releasing same to fire the round.


Practicing trigger pulls without ammo. A very good exercise, but should not be done with rimfire guns, unless the manufacturer states that it is safe for the gun. Otherwise, damage could occur.

Ejection port

On a semi-automatic, the opening in the slide on the right side of the gun through which empty casings are ejected during the firing sequence. These casings will sometimes hit you in the face (hence the need for eye protection) or go down your shirt, and they will definitely hit the person to your right, unless there is a baffle in place. They are not dangerous, just annoying.


Up and down adjustments in aiming, while left and right adjustments are called windage. All scopes have windage and elevation fine adjustments. Most rifles and some pistols have windage adjustments possible (although some are tricky). Pistols typically do not have elevation adjustments available, except for target pistols.


A part in a firearm for removing a cartridge or case from the chamber.


Slang for Eye Protection and Ear Protection, both of which are required at gun ranges.


Federal Fireams License. A Class 1 licensee can buy guns wholesale and sell them retail. While all gun stores have a Class 1 FFL, many such licensees are individuals who work from their homes. There are substantial paperwork requirements, overseen by the ATF. A Class 3 FFL is for firearms collectors. They cannot deal in firearms as a business. The paperwork is less, but the process of acquiring items for the collection is simplified.

Firing Pin

A rod or plunger in a firearm that strikes and thereby detonates a sensitive explosive (found in the primer or cartridge rim) to fire the propelling charge of powder.

Firing Pin Safety Block

An internal device present on many semi-automatics which prevents the gun from being discharged unless the trigger has been depressed. Dropping such a gun will not cause it to fire. In fact, most handguns have multiple internal safety features.

Five Seven

A curious name for a curious handgun caliber that has only recently become known to the general public. The "5.7 x 28" has a very small bullet (about the size of a .22), pushed by a lot of gunpowder. Think "AR-15 out of a handgun". The bullet travels at blistering speed, will penetrate some levels of body armor, but has very mild recoil. Since only one manufacturer made a pistol in this caliber, they were quite expensive, until Ruger introduced a new model. They are becoming more popular, but are still somewhat expensive, especially the ammo.


There is an acquired skill of quickly pointing a gun, getting a sight-picture, and firing, without taking time to carefully align the sights. The purpose is defensive shooting. Experience and instinct are required.


Slang. A flinch is caused by anticipating the report or recoil of a firearm and is usually characterized by a sudden clenching of the hand, which causes the shot to go astray.


The plastic insert in a magazine that pushes the cartridges up for feeding. Applies to semi-automatic pistols, rifles, and shotguns, pump-action shotguns, and magazine-fed bolt-action rifles.


In general, continuing to maintain all aspects of the fundamentals (stance, arm-extension, grip, etc.) past the point at which the shot breaks. More specifically, continuing to pull the trigger back past the break until it hits the frame. In both cases, the goal is to minimize any influence on the muzzle during the shot.


Full Metal Jacket, AKA "range ammo". Ammo where the bullet is enclosed in copper or zinc alloy, so no lead is exposed. These are less expensive than hollow points, and have greater penetration (sometimes too much).

Front Sight Focus

The best accuracy with a handgun is obtained by tightly focusing the vision on the front sight, not the target.


Feet per Second. A unit of measure to express the velocity of a bullet. Handgun bullets typically travel at 800-1200 fps, while rifle bullets often travel at 2000-3000 fps, depending on caliber. Heavier bullets travel slower, so velocity is a better predictor of penetration (and stopping power) than caliber.

FTE (Failure-to-extract)

In an autoloader, the shell just fired is automatically ejected out of the right side. If it doesn't eject at all, that could be a light primer strike, a worn extractor hook, or dirt behind the extractor. If it ejects enough to get caught by the slide returning to battery, that could be a too-strong recoil spring, or dirt in the slide rail, but is often related to not having a firm enough grip on the pistol. See Limp-wristing.


A unit of weight for bullets (bullets, not cartridges), equal to 1/7000 of a lb. Heavier bullets move slower and drop more, but impart greater force. However, the slower velocity mitigates the increased force. See Power Factor.


Both the portion of the pistol that you hold, and the way in which you hold it. Both are important.

Grip Safety

On 1911 pistols (and some others), a pressure point on the backstrap keeps the gun from firing unless it is held properly. It cannot fire if dropped, unless the grip safety is defective. Any type of safety can fail, although they seldom do.


Generally, scoped rifles only. Due to bullet-drop (gravity) or ammo issues, a rifle may shoot either high or low at certain distances. It is often impractical to adjust the scope elevation (or POA) short term, so shooters may employ a "hold" or "hold-over" to correct the POI. If you imagine a circle around the POA, aiming at the bottom of the circle is a "6 o'clock hold" (common), while aiming at the top of the circle is a "12 o'clock hold" (not common). This is typically used to adjust for elevation, but due to wind and distance, holds may be used at 3 o'clock or 6 o'clock. Telescopic scopes contain hash marks on the reticle to assist in this.

Hollow-point (HP)

Bullets with a hollowed out tip, which causes them to expand in flight, and expand more on contact. The media typically thinks these are "cop-killer" rounds, but the intention is actually safety. The larger profile prevents over-penetration, which could cause a bullet to go all the way through a person and hit someone behind them. They were developed at the request of police agencies, to protect the public. A side-benefit is that they cause more surface damage, thus stopping an active shooter sooner.


A device for carrying a handgun. Usually made of leather or Kydex (a plastic-like material), and sometimes fabric or latex, these are important for protecting the trigger guard so nothing snags the trigger. They can be classified as "Inside-the-waistband" (IWB), "Outside-the-waistband" (OWB), i.e., open-carry, pocket holster, shoulder holster, ankle holster, bra holster, or "belly-band". There also exist holster purses for ladies, with a zipper pocket to keep a gun isolated from other contents.


Keeping the index finger of the shooting hand always straight alongside the frame of the gun, and never inside the trigger guard, until a sight-picture is acquired.

Iron Sights

Slang. Standard metallic non-magnifying sights that are built-in on the gun.


Inside the WaistBand, a holster that fits between the belt and body, so the gun is inside the pants. Some models are "tuckable", meaning a shirttail can be tucked between the gun and the belt, so nothing can be seen except the metal hooks on the belt.


The tumbling of a bullet in flight. So named because of the easily identifiable 'keyhole' shaped hole a tumbling bullet often makes in a paper target.


A rigid, plastic-like material frequently used for holsters. Thy are molded for each model of gun, so the gun tends to "lock in", providing both retention capability, and one-handed reholstering. Law Enforcement holsters are almost always Kydex.


An aiming device used on military sniper rifles, but also on many handguns, often as an aftermarket add-on. It projects a red or green laser light beam onto the target, and assists in aiming. They have to be zeroed like a scope. They are often limited in range, and can be impossible to see in daylight.


Common acronym for Law Enforcement Officer.


The proper operation of a semi-automatic requires a minimum amount of recoil from the exploding cartridge to drive the slide back, eject the shell casing, and drive another cartridge into the chamber. If the shooter allows their arm/wrist to act like a spring, some of that force is absorbed, and the slide may not move back far enough to eject the casing. This leads to malfunctions.

Line of Sight

The straight line between an observer's eye and a target. The sights of a firearm need to be in this line.


Acronym for License to Carry, formerly known as CHL.


An iconic German pistol made between 1898-1945, but also a label to describe traditional 9mm (Parabellum) ammunition. Georg Luger developed both the pistol and the 9mm cartridge it fires. Never buy 9mm ammo that is NOT labeled "Luger" without a valid reason. See Makarov.


A detachable container that holds cartridges; not a clip.


Not a private detective, but a cartridge designated to have more powder in it, to produce substantially more muzzle velocity and energy transfer (and recoil). Common examples are the .357 Magnum revolver (much hotter than .38 Special), .44 Magnum (much hotter than .44 Special), and .22 WMR (Winchester Magnum Rimfire), which turns a .22 LR into a rocket. Note that, while the .357 Magnum and .44 Magnum can safely shoot their lesser cartridges, the .22 Magnum cannot.


An unusual variant on the 9mm (9x19) cartridge, the Russian Makarov is slightly shorter (9x18). It should only be fired in a pistol specifically chambered for the Makarov round. This was famously used by the East German "Stasi" Secret Police during the Cold War.

Make Safe

A range command to instruct the student to render the firearm safe by applying the safety or removing the magazine and clearing the chamber, or performing other firearm-specific functions.

Match Grade

Firearms, ammunition, or equipment manufactured to shoot more accurately than similar standard or unaltered ammunition or firearms.


Failure of a round of ammunition to fire after the igniting action has occurred. That usually indicates a bad primer.


Minute-of-angle. A ballistics term used to describe the fact that any error between POA and POI increases with distance to the target. Applies to any type of gun, but is most often used with rifles at 100+ yards. However, pistol shooters should be aware of the issue.

Moon clips

Revolvers require cartridges with rims, so they don't slip through the chambers. Some revolvers are chambered for non-rimmed calibers normally used in semi-automatics (like .45 ACP), so these guns require a metal clip to keep the cartridges in place.


The business end of the barrel.


A pistol or rifle that is about 200 years old, or is a replica of same. These were loaded through the muzzle (the front end), with black powder, then a cloth or paper patch, then a lead ball. That was tamped down with a rod. The ball is typically 50 caliber or bigger, and quite powerful. These replica guns are readily available and very popular for sporting and plinking purposes, but care must be taken, as black powder, unlike gunpowder, is explosive.

Night Sights

Pistol sights utilizing three dots containing a substance like Tritium that glows in the dark. While useful for a nighttime emergency, they will lose their glow after a few years. Seniors may not appreciate the small size of the dots.

Open Carry

Carrying a pistol in a holster that is not concealed from public view. A license is required to do this in some, but not all, states.


The distance the trigger travels after the shot breaks. Less is better. This is sometimes adjustable.


Outside the WaistBand, a holster worn in plain view, like a Police Officer. These are legal in Texas, subject to certain restrictions.

Parallel Zero

Scopes and lasers have to be zeroed to a specific distance. Scopes in particular have a built-in way to adjust for this (holdover), but lasers do not. Lasers are only accurate at the distance at which the device was zeroed. Bot shorter and longer distances will be off by increasingly greater amounts. Many people who use a laser on a handgun, instead, adjust the laser so the beam of light is parallel to the bore axis of the barrel. When this is done, the laser will not be pinpoint accurate at any distance, but the error will always be the same, so the Point of Impact will be about 1 inch high. For self defense purposes, this is fine, and eliminates much of the unnecessary thought process. See zero.

PC Carbine

Pistol Caliber Carbine, a short rifle chambered for some caliber normally associated with pistols. It can be as big as a .45, but is often 9mm, and sometimes .380. They often use magazines compatible with popular pistols like Glock or Ruger. Besides the advantage of sharing ammo across several guns, these are also softer-shooting, and have advantages in close-quarters situations. They are sometimes called "Camp guns" or "bug-out guns".


Slang for fun target shooting, using paper targets, bottles, cans, melons, etc.


Point of Aim. Where you want the bullet to go.


Point of Impact. Location of the bullet hole.

Point Shooting

Shooting without using the sights at all, using specific techniques. This takes practice, and is only viable at very short distances, 3 yards or less.

Power Factor

A calculated number that indicates, in a relative way, the stopping power of a particular cartridge. Stopping power is proportional to both bullet weight and velocity, but those two values are inversely proportional to each other (heavier bullets travel slower), so Power Factor is a metric that takes both into account, with this formula:
pf = w x v / 1000
Power Factor = Weight (in grains) x Velocity (fps) / 1000
A 165 gr bullet traveling at 1100 fps = PF 181.5
A 180 gr bullet traveling at 960 fps = PF 172.8

The two examples above are both .40 cal, but in this case, the lighter bullet hits marginally harder, with less recoil.


A small, concussive detonating device mounted in the base of a cartridge. It is set off by a sharp strike from a small, pointed object, and causes the powder in the cartridge to ignite, generating a large amount of gas. This propels the bullet down the barrel.

Press Check

A method of determining if there is a round of ammunition in the chamber of a firearm. The action is opened slightly and the chamber is examined by sight or touch.


Verb, to pull back the slide on a semi-automatic and allow it to spring forward, loading a cartridge from the magazine into the chamber. Some degree of hand strength is required, although the right technique makes it easier.


The backward movement of a gun when fired, caused by the pressure of the propellant gas. Also the distance that a gun or part travels in this backward movement.

Red Dot

A popular aiming device often used on rifles, and sometimes pistols. It does not project a laser beam to the target (see Laser), but instead projects a red dot onto the image of the target inside the device itself. Consequently, neither distance to the target nor sunlight have any affect on it. It does have to be zeroed like a scope, although it does not magnify the image.


When firing a semi-auto pistol, keep pulling past the break until it bottoms out on the frame. Then let up just a few millimeters until you hear a "click". You are now at the sear wall, and the sear has reset so that you can fire again without lifting your finger off the trigger. "Riding the reset" is a good training exercise.


Retention holsters have special features that make it difficult for someone to grab your gun by force. These can include a thumb strap, the FBI cant (15 degree tilt), and a locking mechanism (Kydex holsters only). Holsters with any of these features are available to civilians, and are usually required for law enforcement officers.


The crosshairs in a telescopic scope, used for aiming. Both crosshairs are often subdivided (hash-marks) to assist in adjusting for bullet drop at a distance.


A spiral groove cut into the bore of the barrel. This imparts spin to the bullet and contributes to greater accuracy, especially with rifles. It is similar to the spin of a football. Lighter or heavier bullet weights require different rates of twist of the rifling for greater efficiency.


Due to the small size, .17 and .22 caliber guns (pistols and rifles) have the primer embedded in the rim of the base of the casing, instead of the center. The firing pin has to hit the cartridge on the rim to fire it. Consequently, dry-firing guns of this type may damage the firing pin, as, without a shell casing in the way, the firing pin would hit the edge of the chamber.


Range Safety Officer. An individual with specialized training for managing a firing line with multiple shooters. If the number of people shooting is more than about 8, he may have some assistants. Always used at outdoor ranges, and often at indoor ranges. The RSO has a critical role in establishing and maintaining a set of rules and policies that will keep everyone safe. He/she has full authority to remove someone from the range if necessary. They are usually armed, for good reason.


A mechanical device on some semi-automatic pistols which prevents the pistol from shooting. While failure of this device is quite rare, you should never trust it with your life. They are usually mounted near the right thumb (ambidextrous safeties can be reached with either thumb), but are sometimes built into the grip (grip safety), so that the pistol has to be held properly to be fired. Hammer-fired pistols will always have either a safety or decocker. Striker-fired pistols, having less sensitive triggers, may or may not. The models carried by police seldom have safeties.


Short-barrelled rifle, a rifle with a barrel shorter than 16 inches, or overall length less than 26 inches. These are restricted the same as suppressors and machine guns, requiring deep background checks, a $200.00 tax, and lengthy wait times, often 6 months.


Often used on rifles, but seldom on pistols, a scope magnifies the target from 3 to 15 times or more. Crosshairs assist in aiming. They can be quite expensive, often costing more than the gun, and require zero calibration at a specific distance. That is best done by an expert.


The part of the trigger mechanism that holds the hammer or striker back until sufficient pressure has been applied to the trigger, at which point the hammer or striker is released to strike the firing pin and discharge the weapon.

Sear wall

On semi-auto handguns with two-stage triggers, a point about 1/2 of the way through the trigger stroke where there is a stopping place, or "wall". Moving to this point is called "preparing the trigger". From this spot, exerting more pressure causes the trigger to ease over that wall to the break, which fires the gun. Doing this gently allows you to fire the gun without letting the muzzle move off the target.


Combat rifles have a rotary switch on the left side, operated by the thumb, which allows the operator to "select" semi-auto mode or full-auto (sometimes burst mode). By Federal law, models available for purchase by the general public cannot have this feature. They are, however, used by law enforcement and the military.


The distance from the rear sight to the front sight. The shorter the sight-radius, the higher the degree of aiming error, multiplied by the distance. That is why longer-barreled pistols (and rifles) are more accurate at longer distances.


AKA Iron Sights. The front and rear sights permanently attached to most pistols. They are usually adjustable, although sometimes not easily.


The combination view of rear sight, front sight, and target. The components must be aligned properly.


See Suppressor.

Single stack magazine

A slender pistol magazine that accepts cartridges only in a vertical stack. These hold less ammo than a double stack magazine, but that allows the grip to be thinner, often an advantage for concealability.


When a pistol is cocked, and only a short trigger pull is required to fire it, it is said to be in single-action mode. Some pistols (revolvers) have to be manually cocked to be in this state, while some autoloaders are always in single-action mode after the first shot. Striker-fired guns are always in single-action.


The amount of movement in a trigger mechanism before it engages the sear. Also known as "take-up".


On an autoloader, the upper part of the gun, which moves back and forth on rails to load and eject cartridges. One should keep their hands away from the slide while firing.


If you put the support-hand thumb behind the slide on an autoloader, you are likely to be struck by the slide as it cycles. It is not fatal, but hurts a lot, and tends to bleed profusely. People tend to only be "bitten" once, as they quickly learn a valuable lesson.


On a semi-automatic, when the magazine is empty, the slide locks open. Reloading from slidelock is slightly slower than reloading with a round in the chamber (Tactical Reload), as you must insert the mag AND close the slide.


A firearm with no rifling in the barrel, such as a shotgun or musket.


A liquid capable of dissolving powder residue and used in the cleaning of firearms. The best-known is Hoppe's #9.


Dummy cartridges used to test the action (loading/unloading) of pistols. They do nothing at all, and are often painted a bright red or blue.


For semi-automatics, a device for assisting in pushing cartridges down into a magazine. Almost mandatory for some pistols. For revolvers, a device that holds 5 or 6 cartridges for quick insertion into the cylinder.

Squib, or Squibload

Manufacturing error, where a cartridge contains no gunpowder. When fired, the primer is strong enough to push the bullet out into the barrel. The sound is quite abnormal. If you fire again without clearing the obstruction, you will ruin the barrel.


The basis of your shooting platform; the way you stand and position your body. The Weaver stance was in common use by law enforcement for many years, but that has largely been replaced now by the Isosceles stance.


Bullets are traditionally made of lead, and often coated with copper or zinc compounds. Steel-core bullets are made of steel. They are not more lethal, just cheaper. They are banned by many ranges, as they pose a fire hazard from sparks when they hit concrete.


Where hammer-fired pistols use an external hammer to drive the firing pin into the rear of the cartridge, firing the primer which ignites the powder in the cartridge, striker-fired pistols have a firing pin that is spring-loaded. Racking the slide puts partial spring pressure on the striker, but not full pressure. Pulling the trigger adds the additional spring pressure necessary to fire the gun. While it may not be accurate to say that striker-fired guns are safer than hammer-fired ones, it is safe to say that they are more "idiot-proof". They never have decockers, and seldom have safeties, so there is nothing to remember: just point and shoot (if it has been racked). Most modern pistols are striker-fired. Hammer-fired guns are still made by some companies, including CZ, Beretta, SIG Sauer, Kimber, and all 1911s.

Stripper clips

Typically used in WWII combat rifles, these clips hold a stack of 5-8 cartridges together. The assembly is pushed into the rifle from the top, as the magazine is non-removable.


Slang for an ejected casing that gets caught by the slide before it is fully clear of the gun (see FTE).


Bullets that travel below the speed of sound (1125 fps) do not break the sound barrier, so are quieter. These are primarily .22 and .45 caliber, although even those may be overloaded with powder, or use lighter bullets, to reach supersonic speeds. The length of the barrel is also a factor, as longer barrels generate more speed. This is mostly important to people who use a suppressor, since the loudest component of a gunshot is the crack when the bullet breaks the sound barrier. Subsonic .22 rounds, fired through a short barrel, and through a suppressor, can be almost inaudible.


A cylindrical device that screws onto the end of a pistol/rifle barrel to reduce the sound of a gunshot. It does so by diverting the gasses from the muzzle blast through a series of baffles. Also known as a silencer (or can), these are regulated by the ATF, under the provisions of the National Firearms Act of 1934. They are legal to own, but require a lot of paperwork that takes at least 4 months. They are most effective with rimfire calibers.

Sweeping the line

On a firing line, turning around (or to the side) without properly controlling the muzzle, so that it passes across one or more people. This is extremely dangerous, a huge breach of protocol, and will often result in you being ejected from the range. It will also cause you to be treated like a moron. The muzzle must always point downrange. Serious shooters are always conscious of this.


A sense that events have gone into slow motion, frequently encountered by people in gun fights. This can lead to confusion in police statements, which in turn can be interpreted as the shooter "changing his story". Defining an exact timeline should always be delayed for one sleep cycle.

Tap, Rack and Roll

The solution to most malfunctions on semi-automatic pistols: hit the bottom of the magazine, roll the gun over to the weak side, and rack the slide.


The distance the trigger travels before contacting the sear. Less is better for target shooting, but more is better (within reason) for safety purposes. Also known as "slack".


A high powered Soviet cold-war period pistol round (7.62x25), and used generically as a label for guns that fire this round. It is smaller than a 9mm, but much more powerful. Originally Russian, the TT-33 pistol was, after WWII, produced in all the Soviet-bloc and Warsaw Pact countries (Poland, Romania, Hungary, Yugoslavia, China), and then imported into, or manufactured in, many other countries. Almost identical copies of the Polish/Romanian/Chinese Tokarevs can now be found in Egypt, Syria, Libya, Pakistan, central Africa, Viet Nam, and other parts of the Pacific Rim. Although it has many of the design features of the iconic John Browning 1911, it is relatively rare in the U.S. Nevertheless, it is one of the most prolific models of pistol in the world.

Tracer rounds

Normally only used in machine guns, where every fifth round is coated with magnesium. Friction from the air makes them glow, so the gunners can see the path of fire. They have no useful purpose for civilians, but they have started fires at ranges. They are always banned from civilian ranges, but sometimes an idiot will sneak some in.


The lever that releases the hammer/striker to strike the back of the cartridge. You must not touch the trigger until you are in position to shoot. The trigger guard protects the trigger from being snagged by clothing or holsters.


The distance in inches a bullet travels through the barrel to make one complete revolution. Expressed as a ratio such as 1:8, meaning one revolution in 8 inches. The twist rate needs to match the weight of the bullet you plan to shoot (especially rifles), or the bullet may wobble badly in flight.

Wheel gun

Slang for a revolver.


Left and right adjustments in aiming, while up and down adjustments are called elevation. All scopes have windage and elevation fine adjustments. Most rifles and some pistols have windage adjustments possible (although some are tricky). Pistols typically do not have elevation adjustments available, except for target pistols.

Zero/Zeroing/Zero Calibration

Without getting too deep into the physics, an aiming device (scope/laser/red dot) cannot operate on a plane parallel to the plane of the bullet path (itself not flat), or the POA and POI will never intersect. Instead, the aiming plane is angled to intersect the plane of the bullet, at a specific distance, often 100 yds (rifle) or 25 yds (pistol). Consequently, the POI will be either high or low at other distances, so the shooter has to adjust manually. See parallel zero.


Technique for using a small caliber pistol (.22/.32) in a defensive situation. Inasmuch as these rounds have little stopping power, instead of shooting 2-3 times to the same area, shoot 6-10 times rapidly in a pattern from the chest down to the lower torso, the "zipper" effect. If the wounds are not fatal, the bad guy will at least be in serious trouble, as he will be bleeding from multiple places, and will not be able to stop the bleeding easily. This technique was developed by partisan guerillas during WWII for taking out sentries at Nazi locations like railway stations and ammo dumps.

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