Letter S

The Definition of Sight Alignment

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Sight Alignment

The manner in which the sights are lined up properly in front of the shooter's eye, to form a straight path to the target.


19 Other Firearms Definitions You Need To Know


Autoloader

A firearm that automatically loads the next cartridge to be fired into the chamber either upon the pull of the trigger in an open bolt design or upon the firing of the previous round in a close bolt design.
Autoloader should not be confused with Automatic or Semi-Automatic since the term Autoloader only applies to how the next round is chambered not how many rounds can be fired per trigger pull. All Automatic and Semi-Automatic firearms are autoloaders. Revolvers, bolt action, lever action and pump action firearms are not autoloaders.

Chapman Stance

The Chapman stance uses the same push-pull tension which defines the Weaver, but instead of both elbows being bent, the gun side elbow is held straight and locked in place. Assuming a right-handed shooter, the right arm is punched straight out, while the left elbow is bent and the left hand pulls back to provide tension. As a result of this change, Chapman gets its stability from both muscle and skeletal support. This makes it a little more friendly than Weaver for those who lack upper-body muscle strength.

Line Of Sight

An imaginary straight line from the eye through the sights of a firearm to the target.

Boresight (Bore Sight)

Crude adjustments made to an optical firearm sight, or iron sights, to align the firearm barrel and sights. This method is usually used to pre-align the sights, which makes zeroing (zero drop at XX distance) much faster.

Stovepipe

Failure of a spent case to completely eject from a semi-automatic firearm. The case usually stands on end while lodged in the ejection port.

Ejector

A spring-activated mechanism for the ejection of ammunition or and empty shell casing. On doubles, each barrel has a separate ejector.

Lockplate

A metal plate on which the firing mechanism is mounted on percussion and earlier firearms.

Casehardening

A heat-treating process that incorporates carbon into the surface molecular structure of the steel, providing a hard-wearing surface without making the entire receiver brittle. The parts to be casehardened are packed in a crucible with carbon-rich media such as bone meal and charcoal, heated to bright orange, about 1800F, then quenched in bubbling oil. Also called Carbonizing.

Rimless

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.

Cant

To tilt a gun to one side or the other, complicating sighting considerably. Can cause material loss of accuracy, particularly with a rifle at longer ranges. Some better long range target rifles are equipped with Spirit Level sights to help control canting.

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.

Underlug

The locking lugs on a break-action firearm that extend from the bottom of the barrels under the chamber(s) and connect into the receiver bottom.

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.

WCF

Abbreviation for Winchester Centerfire.

Drift

The departure of a bullet or shot charge from the normal line of flight. This can be caused by wind or the unbalanced spinning of the bullet.

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.

Kentucky Rifle

Usually referred to as a Kentucky Long Rifle or simply Longrifle, the Kentucky Rifle is a flintlock rifle with a long barrel and short, crooked stock. It is widely believed to be a largely unique development of American rifles that was uncommon in European rifles of the same period. The Kentucky Long Rifleis an early example of a firearm using rifling, (spiral grooves in the bore). This gave the projectile, commonly a round lead ball, a spiraling motion, increasing the stability of the trajectory. Rifled firearms saw their first major combat usage in the American colonies during the Seven Years war, and later the American Revolution in the eighteenth century.

Flashbang (grenade)

A stun grenade, also known as a flash grenade, is a non-lethal explosive device used to temporarily disorient an enemy's senses. It is designed to produce a blinding flash of light and intensely loud noise "bang" of greater than 170 decibels (dB) without causing permanent injury. It was first developed by the British Army's SAS in the 1960s.
The flash produced momentarily activates all photoreceptor cells in the eye, making vision impossible for approximately five seconds, until the eye restores itself to its normal, unstimulated state. The loud blast is meant to cause temporary loss of hearing, and also disturbs the fluid in the ear, causing loss of balance.
The concussive blast of the detonation can still injure, and the heat created can ignite flammable materials such as fuel. The fires that occurred during the Iranian Embassy siege in London were caused by stun grenades.

Semi-Wadcutter

A bullet design featuring a conical extended nose, with a flat point, and a sharp edged shoulder that serves to cut a full diameter hole in the target. This design also may be found with a hollow point to facilitate expansion. A modified wadcutter bullet design with slightly sloping edges, designed to load smoothly in a semi-automatic pistol.