Letter D

The Definition of Drum Magazine

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Drum Magazine

A type of firearms magazine that is cylindrical in shape, similar to a drum. Probably the most recognizable drum magazine is the magazine for a Thompson carbine rifle, also known as the Tommy Gun.


19 Other Firearms Definitions You Need To Know


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.

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."

Plus P

Also spelled "+P" or "P+". Is small arms ammunition that has been loaded to a higher internal pressure than standard for it's caliber. Many calibers are available in both standard and +p or +p+ variants. Ammunition marked +p produces more power and higher pressures than the standard ammunition. Not all firearms are designed to handle the increased pressure consult your owner's manual or gun manufacturer before using +P ammunition.

Eye Dominance

Although we have two eyes for depth perception and for spare parts, there is a natural tendency for one eye (the master eye) to take precedence over the other, regardless of the relative visual acuity of each eye. It is a fortunate condition when the eye on the side of the shoulder where one is comfortable mounting a gun is also the dominant eye.
To test for eye dominance:

Pick out a small object several feet away. With both eyes open, center your right index finger vertically over the object. Close your right eye. If your finger appears to jump to the right, you are right eye dominant. Then open your right eye and close your left eye. If your finger remains in position in front of the object, you have confirmed your right eye dominance. Alternatively, if in the above test, upon closing your right eye your finger remains in position covering the object, you are left eye dominant. If you close your left eye instead and your finger appears to jump to the left you have confirmed your left eye dominance.
Eye dominance problems can be treated with
1. A severely-cast, crossover stock to bring the dominant eye in line with the gun's line of sight, 2. A patch over the dominant eye, or just a small piece of frosty Scotch tape on shooting glasses intercepting the dominant eye's line of sight, 3. Fully or partially closing the dominant eye, or 4. Learning to shoot from the dominant-eye shoulder.
While less convenient, methods that retain the use of both eyes better preserve the ability to perceive depth in three-dimensional space, a great benefit in wingshooting.

Breech

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

Grain

A unit of weight widely used to express the weight of bullets and of powder charges. Equal to 1/7000 pound.

CCP

Abbreviation for Concealed Carry Permit.

Extractors

A part in a firearm that serves to remove brass cases of fired ammunition after the ammunition has been fired. When the gun's action cycles, the extractor lifts or removes the spent brass casing from the firing chamber.

Barrel

A tube, usually metal, through which a controlled explosion or rapid expansion of gases are released in order to propel a projectile out of the end at a high velocity. It is the tube through which the bullet or shot travels. The barrel serves the purpose of providing direction and velocity to the bullet.

Damascus Barrels

Barrel tubes built up by twisting alternate strips of iron and steel around a fixed rod (mandrel) and forge-welding them together in varying combinations according to the intended quality and the skill of the maker. The rod was withdrawn, the interior reamed and the exterior filed until the finished tube was achieved. Damascus barrels may be recognized by any of a variety of twist or spiral patterns visible in the surface of the steel. Before the 20th century, barrels were typically built in this manner because gunmakers did not have the technology to drill a deep hole the full length of a bar of steel without coming out the side.

Isosceles Stance

There are two basic variants of the Isosceles stance, the Traditional Isosceles and Modern Isosceles stance. In both Isosceles stances, the feet parallel pointing toward the target and are roughly shoulder width apart. Both arms are stretched almost equally forward with the gun centered forward, creating the triangular shape which gives the stance its name.

Butt

The rear end of a rifle or shotgun. (The portion that rests against the shoulder.)

Negligent Discharge

The unplanned discharge of a firearm caused by a failure to observe the basic safety rules, not a mechanical failure of the gun.

Trigger Lock

A locking device, usially a clable with a padlock that you put on a firearm to render it unable to be fired buy running it through the magazine well and out the ejection port.

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.

Corto

Italian for "short." Seen as part of a cartridge designation. On some Italian manufactured guns that use .380 ACP, the designated caliber is 9mm Corto (9mm Short), which is also the same as the German 9mm Kurtz

High-Capacity Magazine

An inexact, non-technical term indicating a magazine holding more rounds than might be considered "average.".

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

Repeater

A type of firearm capable of discharging multiple individual shots in sequence, fed from a magazine, via the operation a lever, bolt, slide or some other form of manual operation.