Letter J Firearms Glossary

Arsenal Exchange - Firearms Classifieds - Industry Directory

Jacket

A metal, usually copper, wrapped around a lead core to form a bullet.

Jam

A malfunction which locks up the gun so badly that tools are required in order to fix it. Sometimes used to denote a simple malfunction, but many people make a distinction between a complete jam and a simple malfunction.

Jaws

The vise-like device on a flintlock hammer used to hold the flint.

Jeweling

A cosmetic process to enhance the looks of firearm parts, such as the bolt. The look is created with an abrasive brush and compound that roughs the surface of the metal in a circular pattern.

JSP

Abbreviation for jacketed soft point

Jump

The amount of change in the bore axis, measured both vertically and horizontally, while the projectile moves from the chamber to the muzzle when it is fired.


14 Other Firearms Definitions You Need To Know


Light Double Action

A double-action semi-automatic firearm which is designed to have a much lighter trigger pull than is usual for a double action.

Bersa

A firearms manufacturer located in the city of Ramos Mejia in Argentina. The company was founded in the mid-1950s by Italian immigrants Benso Bonadimani, Ercole Montini and Savino Caselli, all of them mechanical engineers with experience working for Beretta. Bersa is most famous for their Bersa Thunder .380 pistols and the Thunder Ultra Compact Pro Pistols (available in 9mm, .40 S&W and .45 acp). The full size Thunder combat (Thunder 9) pistol is the standard sidearm of the Argentina Armed Forces, Buenos Aires Provincial Police and several other law enforcement agencies in South America. The company is well known among firearm enthusiasts for producing high quality guns at reasonable prices and it spends little money on advertisement. Lifetime warranty coverage is provided to the original owners. They are strong and well built, nicely engineered, accurate, visually appealing and very reliable.

Trigger Safety

An external, passive safety which can be found on the face of some trigger designs (most notably found on Glock firearms). It is intended to prevent the trigger from being pulled by objects which find their way into the trigger guard area.

Improvised Firearm

A firearm manufactured by someone who is not a regular maker of firearms.

Skeet

A shotgun shooting sport in which the competitors attempt to break aerial targets directed toward them or crossing in front of them from different angles and elevations. It is an Olympic shooting sport.

Long Rifle

Typically used in the .22 caliber cartridge designation .22 Long Rifle, which is abbreviated .22LR.

Traditional Isosceles

In the Traditional Isosceles stance, Both arms are stretched almost equally forward with the gun centered forward. The knees are straight or only slightly flexed, and the entire body is upright and parallel to the target. This is an acceptable range stance provided recoil control is not an issue and you don't need to make rapid follow-up shots. However, if you are practicing for self-defense, you will probably want to use the Modern Isosceles stance stance instead.

Ammo

Slang word abreviation for Ammunition.

Soft Point

A metal jacketed bullet design in which the nose of the core of the bullet is exposed to ensure the expansion of the bullet upon impact. Often abbreviated "JSP" or "SP." They tend to expand more slowly than a Hollow Point bullet and are used where deeper penetration and expansion are needed.

Pull

The entire process of making the trigger complete its journey past the trigger break.

Cal

Abbreviation for Caliber.

Trigger Bar

On a semi-automatic pistol, or any other firearm in which the trigger is at some distance from the sear, this is an intermediate piece connecting the two parts.

Adjustable Trigger

A trigger that can be easily adjusted by the user. Adjustable triggers are common on specialized target-shooting firearms.

Ball

Originally used to describe the spherical projectile used in black powder firearms, now also used to refer to a fully jacketed bullet of cylindrical profile capped with a round nose