Letter L

The Definition of Locking Lugs

Arsenal Exchange - Firearms Classifieds - Industry Directory

Locking Lugs

A series of projections on the bolt of a firearm designed to fit into corresponding slots in the receiver to lock the action in closed position for firing.


19 Other Firearms Definitions You Need To Know


Wadcutter

A bullet designed with a full diameter flat point. It is primarily used in target competition because it cuts a clean round hole in paper targets that aids in scoring the target.

Magazine Well

The opening in the bottom of the gun into which a box magazine is fed. On a semi-auto handgun, the magazine well is at the base of the grip; on a rifle, it is usually placed in front of the trigger guard.

Smokeless Powder

The propellant powder used in modern ammunition. It is not an explosive, but rather a flammable solid that burns extremely rapidly releasing a large volume of gas. Commonly called "gunpowder" and usually made from nitrocellulose, or nitrocellulose and nitroglycerin. It is classified as a "Flammable Solid" by the Department of Transportation.

Key Fastener

A horizontal wedge, press-fit through the forend of a vintage gun, through a lump attached to the underside of the barrel and out the other side of the forend. To secure the forend in position. Also called a crosspin or a wedge fastener.

M1911

The official US military designation for the Colt .45 semiautomatic pistol adopted by the US in 1911. The gun was designed by John Moses Browning, and produced by Colt. During trials, the Browning-Colt design beat out several competing designs, including one from Savage and a .45 caliber version of the German Parabellum ("Luger"). The M1911 saw its first combat in the Philippines and then in World War I. Early use showed that it could be improved and in 1921 the M1911A1 was introduced, which featured a few changes like a reocontoured frame, shorter trigger, and a rounded backstrap. The M1911A1 remained the standard US military handgun until it was replaced in the 1980's by the Beretta M9. However, it remains very popular with civilian shooters in the US, and has been modified extensively to update it to conform to more modern theories of handgun usage.

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.

Cal

Abbreviation for Caliber.

Trigger Break

The point at which the trigger allows the hammer to fall, or releases the striker, so that the shot fires. The ideal trigger break is sudden and definite. "Like a glass rod" is the cliche term shooters use to describe the ideal crisp, clean break.

Crown

The area inside the bore nearest to the muzzle.

Birdshot

A type of shotgun ammunition which uses very small pellets with individual projectiles of less than .24" in diameter designed to be discharged in quantity from the shotgun. The size of the shot is given as a number or letter-- with the larger number the smaller the shot size. It is so named because it is most often used for hunting birds. The finest size generally used is #9 which is approximately .08" in diameter and the largest common size is #2 which is approximately .15"

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.

Fouling Shot

A fouling shot is a shot fired through a clean bore, intended to leave some residue of firing and prepare the bore for more consistent performance in subsequent shots. The first shot through a clean bore will behave differently from subsequent shots through a bore with traces of powder residue, resulting in a different point of impact.

Second Amendment

The second article in the United States Bill of Rights which states, "A well regulated militia being necessary for a free state, the right of the people to keep and bear arms shall not be infringed."

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.

Sectional Density

The relationship between a bullet's weight and its diameter. A long bullet, such as the original 7.62x54R loading for the Mosin Nagant 91/30, will have a high sectional density and consequently greater penetration than a shorter bullet of similar construction. A shorter bullet with less sectional density will have relatively less penetration, but greater knockdown power.

Caliber

The diameter of the bore of a firearm measured as a fraction of an inch. Although such a measurement may be frequently stated in millimeters. It is correctly expressed as ".40 caliber" (note the decimal point) or as "10 millimeter" (without "caliber" or the leading decimal point). Caliber numbers when used to identify the size of the bullet a gun will file are usually followed by words or letters to create the complete name of the cartridge. These letters often represent a brand name or an abbreviation for the name of the company that first introduced the round.

Energy

The amount of work done by a bullet, expressed in foot pounds.

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.

Feed Ramp

An inclined, polished area on a repeating firearm, just behind the chamber, that helps guide a cartridge into the chamber when pushed forward by the closing bolt or slide.