Letter B

The Definition of Blown Pattern

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Blown Pattern

A shotgun pattern with erratic shot distribution, generally caused by gas escaping past the wads and getting into the shot.


19 Other Firearms Definitions You Need To Know


Clip

A clip IS NOT a magazine. A clip is used to load a magazine.
A clip is a simple, disposable narrow spring-lined channel-rail that is used to store multiple rounds of ammunition together as a unit, ready for insertion into the magazine of a repeating firearm. This speeds up the process of loading and reloading the firearm as several rounds can be loaded at once, rather than one round being loaded at a time. The term clip commonly refers to a firearm magazine, though this usage is absolutely completely totaly 100% incorrect. In the correct usage, a clip is used to feed a magazine or revolving cylinder, while a magazine or a belt is used to load cartridges into the chamber of a firearm. in which cartridges are supplied for military weapons. The shooter positions the clip vertically above the firearm's magazine, then pressing down with the thumb, slides the cartridges from the clip and down into the magazine.

Hook

A concave, semi-cylindrical surface cut into the forward lump of a barrel set of a break-open firearm which revolves about the hinge-pin when the gun is opened.

Ballistic Fingerprint

A fired case has marks upon it that it picked up from the extractor, ejector, and breechface of the gun when the shot went off. A bullet fired through a rifled barrel also has rifling marks unique to the barrel that launched it. A record of these marks, when stored in a central database, is called a ballistic fingerprint. Some states require this record to be made by law, so that individual guns can be located from bullets or casings found at the scene of a crime.

OTM

Abbreviation for Open Tip Match.

POI

Abbreviation for Point of Impact

Range Finder

A device used to determine the range to a target. Many range finders 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.

Lug

Any piece that projects from a firearm for the purpose of attaching something to it. For example barrel lugs are used to attach a break-action shotgun barrel to the action itself. If the firearm is a revolver, the term may also refer to a protrusion under the barrel that adds weight, thereby stabilizing the gun during aiming, mitigating recoil, and reducing muzzle flip. A full lug extends all the way to the muzzle, while a half lug extends only partially down the barrel. On a swing-out-cylinder revolver, the lug is slotted to accommodate the ejector rod.

Trigger

The small lever on a cartridge firearm, which one pulls to cause the spring-loaded firing pin to impact the primer, causing the gun to discharge. Normally, the trigger simply connects to the sear. Pulling the trigger moves the sear out of its notch, releasing the spring-loaded hammer to strike the firing pin which in turn strikes the primer; or the coilspring-loaded firing pin directly. Other, often-Germanic systems have their own miniature lockwork which, when cocked, allows an exceedingly light trigger pull to discharge the firearm, a setting that would be perilous to carry in the field.

Ammo

Slang word abreviation for Ammunition.

Small Bore

Generally refers to a .32 calibre or smaller firearm.

Dry Fire

To pull the trigger and release the hammer of a firearm without having a cartridge in the chamber.

Heel & Toe Plates

Protective plates, usually of steel or horn, covering the top and bottom of a gunstock's butt only (the heel and the toe); leaving wood exposed in the center

Windage

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

Kick

Slang for Recoil.

Magazine

A secure storage place for ammunition or explosives. On a firearm, it is the container, either fixed to a firearms's frame or detachable, which holds cartridges waiting to be fed into the gun's chamber.
Detachable magazines for the same gun may be offered by the gun's manufacturer or other manufacturers with various capacities. A gun with a five-shot detachable magazine, for instance, may be fitted with a magazine holding 10, 20, or 50 or more rounds.
Box magazines are most commonly located under the receiver with the cartridges stacked vertically.
Tube or tubular magazines run through the stock or under the barrel with the cartridges lying horizontally (like on a shotgun or lever action rifle.
Drum magazines hold their cartridges in a circular mode (for example the famous drum magazine on a Thompson submachine gun).
On a revolver, the magazine is known as the cylinder.
Internal magazines are built into the firearm and are not removable. Examples of internal magazines are the tube magazines of a shotgun or the magazine on a Mosin Nagant.
A magazine is not a clip!

Elevation

The setting on the sights of a firearm that controls the vertical placement and 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.

Velocity

The speed at which a projectile travels. Velocity is usually measured in feet per second or metres per second.

Parabellum

Latin word meaning "for war." It is actually the proper name of the semiautomatic pistol commonly known in the USA as the "Luger. Because of that pistol and the ammunition created for it, the common 9mm cartridge used nowadays is also known as 9mm Parabellum or 9mm Luger."

Follow Through

Holding the trigger to the rear after the shot has fired, until the sights are back on target, at which time the trigger is released.