Letter O

The Definition of Obturation

Arsenal Exchange - Firearms Classifieds - Industry Directory

Obturation

The process of a bullet expanding under pressure to fit the bore of the firearm, or a cartridge case expanding under pressure to seal the chamber.


19 Other Firearms Definitions You Need To Know


Backstrap

The rearmost surface of the grip on a handgun. the term originated with old pistols. The grips surrounded the frame, making the rearmost of the frame appear as a strap.

Belt Fed

A firearm, usually (but not always) a fully automatic rifle, that uses a ammunition on a belt rather than a magazine to store the rounds that will be loaded into the gun.

Lock

The firing mechanism of a a muzzle-loading weapon. In breech-loading firearms, the lock is the firing mechanism and breech-sealing assembly.

Rifling

Spiral grooves formed into the bore of a gun barrel, which cause the bullet to spin upon firing, thus stabilizing it much like a thrown football. Rifling may be cut, swaged, or forged into the barrel.

Weaver Stance

In the Weaver stance, the body is bladed partly sideways in relation to the target rather than squared towards it (think boxing or martial arts fighter stance). The elbows are flexed and pointed downward. The strong-side arm is slightly straighter than the weak-side arm. Even though the legs are not square to tharget, the hips should be square to the target. The feet should be pointed at the target. The shooter pushes out with the gun hand, while the weak hand pulls back. This produces a push-pull tension which is the chief defining characteristic of the Weaver stance.

ACP

The abbreviation for Automatic Colt Pistol. It is commonly used to designate specific calibers, particularly those which were originally designed by John Moses Browning for the Colt Firearms Company which are a type of rimless pistol cartridge designed mainly for use in semi-automatic pistols. The most common ACP calibers are .25 ACP, .32 ACP, .380 ACP and .45 ACP.

Pinfire

An early form of complete, self-contained cartridge. It included bullet, powder and ignition primer, all in one package. The primer was located towards the base of the cartridge, but completely internally. The pin, shaped like a little finishing nail, pointed on the inside end and resting on the internal primer, projected radially about a quarter-inch to the outside of the base of the cartridge. When loaded, a pinfire gun showed the tips of the pins exposed through small slots in the tops of the breech faces of the barrels. To fire, hammers fell on the pins, driving them (through the wall of the cartridge) into the internal primer.

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.

Igniting Charge

The charge used to ignite the propelling charge.

Trigger Group

The entire collection of moving parts which work together to fire the gun when the trigger is pulled. It may include trigger springs, return springs, the trigger itself, the sear, disconnectors, and other parts.

Shotshell

Same as a Shotgun Shell.

Leading

Fouling of a firearm bore by metal particles from bullets adhering to the metal surface caused by heat or friction.

Mirage

A tendency for layers of air of different temperatures near the warm ground to cause refraction in the line of sight and disturbance of the perceived point of aim.

Load

A charge of powder, a projectile or a cartridge. Also, to prepare a gun for firing by inserting ammunition into it.

Ballistic Coefficient

A measure of projectiles ability to overcome air resistance in flight. It is inversely proportional to the deceleration—a high number indicates a low deceleration. Ballistic Coefficient (abbreviated as BC) is a function of mass, diameter, and drag coefficient. In bullets it refers to the amount that drop over distance and wind drift will affect the bullet.

LMG

Abbreviation for Light Machine Gun

Brick

A box of ammunition roughly equal in size and weight to a brick. Most often used to describe a 500-round container of .22 Long Rifle ammunition.

Cross Dominant

This means a shooter who is right-handed but left-eyed, or left-handed and right-eyed.

Porting

Openings at the muzzle end of the gun through which some of the spent gases can escape. Porting reduces perceived recoil and lessens muzzle rise but increases the noise and flash.

You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 1