Letter R

The Definition of Red Dot Sight

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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.

19 Other Firearms Definitions You Need To Know


The lock that preceded the 'true' flintlock in both rifles and pistols in the 17th century. Commonly used throughout Europe in the 1600s, it gained popular favor in the British and Dutch military. A doglock carbine was the principal weapon of the harquebusier, the most numerous type of cavalry in the armies of Thirty Years War and the English Civil War era.

Turk's Head

A tip for a cleaning rod, a jag, with spirally-radial wires for vigorously scrubbing a gun's bore.

Express Sights

"V" shaped rear leaf sights mounted to a rifle barrel on a block or on a quarter-rib, sometimes solid standing, sometimes folding, and often mounted in a row of similar leaves, each of a slightly different height, marked with the range for which each is regulated


A small piece of leather or cloth. A patch can refer to the wadding used in loading a muzzle loading firearms or the piece of cloth used to clean a firearm bore.


A cartridge in which the base diameter is the same as the body diameter. The casing will normally have an extraction groove machined around it near the base, creating a "rim" at the base that is the same diameter as the body diameter.

Caseless Ammunition

A type of small arms ammunition that eliminates the cartridge case that typically holds the primer, propellant, and projectile together as a unit.

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.

Cylindro Conoidal Bullet

A hollow base bullet, shaped so that, when fired, the bullet will expand and seal the bore. It was invented by Captain John Norton of the British 34th Regiment in 1832, after he examined the blow pipe arrows used by the natives in India and found that their base was formed of elastic locus pith, which by its expansion against the inner surface of the blow pipe prevented the escape of air past it.

High Brass

By convention, powerfully loaded shotgun cartridges for hunting are generally manufactured with relatively longer brass end-caps than lower powered cartridges intended for target shooting. While different-sized brass bases are of virtually no consequence to the strength of the shell in relation to the steel breech of the gun itself, they do help the shooter identify the relative power of cartridges at a glance.

Over Travel

If the trigger is able to continue moving to the rear after the shot has fired, the trigger is said to over-travel.


An underpowered powder charge, usually caused by a fault in cartridge loading, often insufficient to expel a projectile from the muzzle of a firearm. If such a blockage is not cleared, the next attempted shot could cause the barrel at least to bulge, and very possibly to burst.

Double-Set Trigger

Usually only found on black powder muzzle loading rifles and pistols, pulling the rear (set) trigger converts the front (main) trigger to a light, hair trigger (too light and sensitive to be carried safely in the field). While the front trigger is always at the ready, if one has the time, using the set trigger feature may allow for a more accurate long-distance shot. Operates using its own miniature firing mechanism (sear, spring and hammer) when cocked, to multiply the force of a pull on the main trigger.


The cross-shaped object seen in the center of a firearm scope. Its more-proper name is reticle.


Short for the word Ambidextrous. Meaning that a feature of a firearms can be used by either hand, for example ambi-safety, ambi slide catch or ambi mag release.

Improved Cartridge

A wildcat cartridge that is created by straightening out the sides of an existing case and making a sharper shoulder to maximize powder space. Frequently the neck length and shoulder position are altered as well. The caliber is NOT changed in the process.


A type of ammunition that utilizes a projectile or projectiles that contain a compound in its base that burns during its flight to provide a visual reference of the projectile's trajectory.


Abbreviation for Concealed Handgun License.


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."


A type of cartridge for a firearm that contains gunpowder but no bullet or shot. When fired, the blank makes a flash and an explosive sound (report). Blanks are often used for simulation (such as in historical reenactments, theatre and movie special effects), training, and for signaling (see starting pistol). Blank cartridges differ from dummy cartridges and snap caps, which are used for training or function testing firearms; these contain no primer or gunpowder, and are inert.