Letter L

The Definition of LDA

Arsenal Exchange - Firearms Classifieds - Industry Directory

19 Other Firearms Definitions You Need To Know


Single Action

An action type that when the trigger is pulled, the only thing the trigger does is drop the hammer (or striker). This applies to both revolvers, semi-automatic and automatic guns. On a single action revolver, the gun must be manually cocked before it can be fired. With semi-automatic and automatic guns that are single action, the only thing the trigger does is drop the hammer, striker or firing pin onto the cartridge. Then the firearm is cocked again when from the recoil of the fired round. A firearm that the gun is cocked and the hammer drops when the trigger is pulled is a double action gun.

Magazine Pouch

Commonly shortened to mag pouch, this is a device to hold extra magazines which fastens to the shooter's belt.

Terminal Ballistics

A sub-field of ballistics, is the study of the behavior of a projectile when it hits its target.

Sporting Firearm

Any gun that can be used in a sport.

Dust Cover

A small hinged or sliding door covering the ejection port of a firearm to prevent detritus from clogging the works.

Red Dot Sight

A type of reflector (reflex) sight for firearms that gives the uses a red light-emitting diode as a reticle to create an aimpoint.

Open Tip Match

A rifle projectile made with the tip of the bullet open as a means of increasing accuracy as compared to standard military bullets that are made with a closed tip and an open base. The are not designed to expand like a hollow point bullet but may fragment.

Forend

One of the three major dismountable components of a break-open gun (the others being the barrel(s) and the action/buttstock) which secures the barrels to the receiver, often houses the ejector mechanism, and for some, provides a handle for the one's secondary hand.

Breechblock

The part in the breech mechanism that locks the action against the firing of the cartridge.

Mortar

An artillery piece used to fire shells over short ranges at very high trajectories.

Direct Impingement

A type of gas operation for a firearm that directs gas from a fired cartridge directly to the bolt carrier or slide assembly to cycle the action.

Folding Stock

A long gun stock that may be doubled over for conveniently compact storage.

Bullpup

A firearm configuration where the magazine and action are behind the trigger.

NFA

National Firearms Act of 1934. Enacted on June 26, 1934, currently codified as amended as I.R.C. ch. 53, is an Act of Congress in the United States that, in general, imposes a statutory excise tax on the manufacture and transfer of certain firearms and mandates the registration of those firearms. The Act was passed shortly after the repeal of Prohibition. The NFA is also referred to as Title II of the Federal firearms laws.
The NFA includes:

  • Requires the registration of all fully automatic firearms.
  • Requires the registration of all "sawed off" rifles and shotguns.
  • Requires the registration of firearm silencers.
  • Imposes a $200 transfer tax on the above items.

Breech Pressure

The amount of rearward force exerted by the propellant gases on the bolt or breech of a firearm action or breech when a projectile is fired. The applied force has both magnitude and direction, making it a vector quantity. This is also known as Bolt Thrust on firearms that are Bolt Action

Mushroomed Bullet

A description of a bullet whose forward diameter has expanded after penetration.

Pellet Gun

An air gun that shoots a skirted pellet.

Comb

The top of a gun's stock, where a shooter rests his cheek when mounting a gun. As it is the top of the stock that determines the position of one's eye, and one's eye is the rear sight on a shotgun, the position of the comb is very important in determining the proper fit of a shotgun.

Primer Ring

Refers to a visible dark ring created by the primers in centerfire ammunition around the firing pin hole in the frame after much use.