Letter B

The Definition of Ballistic Coefficient

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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.


19 Other Firearms Definitions You Need To Know


Trigger Pull

The entire process of moving the trigger from its forward-most position to its rearward-most position, causing the hammer to fall and the shot to fire.

Center Of Mass

For self-defensive shooters, Center Of Mass (COM) represents the area of an attackers torso within which the most vital organs are likely to be disrupted by a gunshot. Shooting to COM is considered the most expedient way to stop an assailant from continuing threatening behavior.

Matchlock

An early system of ignition for muzzle-loading firearms where a priming charge is loaded into a flashpan with a separate, manually-operated cover. To fire, the cover is opened and then a slowly smoldering wick, held in the nose of the curved arm, is lowered by means of a lever (precursor to a trigger) to ignite a priming charge which then ignites the main propellant charge inside the barrel.

Eyes

Slang for eye protection. Referes to either goggles or safety glasses

Browning

John Moses Browning was born in Ogden, Utah on January 23, 1855, and was an American firearms designer who developed many varieties of military and civilian firearms, cartridges, and gun mechanisms, many of which are still in use around the world. Almost all of his design concepts can be found in some form or another in every modern automatic and semi-automatic firearm. He is regarded as one of the most successful firearms designers of the 20th century, in the development of modern automatic and semi-automatic firearms, and is credited with 128 gun patents. He made his first firearm at age 13 in his father's gun shop, and was awarded his first patent on October 7, 1879 at the age of 24.
The Browning Arms Company was founded in 1878 by John Moses Browning and his brother Matthew Sandifer Browning. The company was founded to market the sporting (non-military) designs of John Moses Browning. The company still exists today mostly manufacturing world class shotguns.

Trap

A game of competitive clay pigeon shooting on a formally designed layout. In plan view, one launching machine is located 16 yards in front of a straight line, firing rising targets perpendicular to and away from that line. Five competitors shoot five individual targets at each of five stations along that line. Although each target is presented at slightly randomized vectors, trap emphasizes generally a single type of shot, outgoing and rising, and targets are broken at generally longer ranges than Skeet.

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

Black Powder

Also known as Gun Powder. A mixture of sulfur, charcoal, and potassium nitrate. It burns rapidly, producing a volume of hot gas made up of carbon dioxide, water, and nitrogen, and a solid residue of potassium sulfide. Because of its burning properties and the amount of heat and gas volume that it generates, gunpowder has been widely used as a propellant in firearms and as a pyrotechnic composition in fireworks. Modern firearms do not use the traditional black powder described here, but instead use smokeless powder.

Wildcat Cartridge

A wildcat cartridge, or wildcat, is a custom cartridge for which ammunition and/or firearms are not mass-produced. These cartridges are often created in order to optimize a certain performance characteristic (such as the power, size or efficiency) of an existing commercial cartridge. Developing and using wildcat cartridges does not generally serve a purpose in military or law enforcement; it is more a hobby for serious shooting, hunting, gunsmithing and handloading enthusiasts, particularly in the United States. There are potentially endless amounts of different kinds of wildcat cartridges: one source of gunsmithing equipment has a library of over 6,000 different wildcat cartridges for which they produce equipment such as chamber reamers.

Rim

The edge on the base of a cartridge case which stops the progress of the case into the chamber.

Pistol

Synonymous with "handgun." A gun that is generally held in one hand. It may be of the single-shot, multi-barrel, repeating or semi-automatic variety and includes revolvers.

Necking Up

Expanding the neck of an existing cartridge to make it use a bullet of a different caliber. A typical process used in the creation of wildcat cartridges.

Glock Auto Pistol

A type of .45 caliber ammunition designed in 2002 by Ernest Durham for use in the Glock Model 37.

DA/SA

Abbreviation for Double Action/Single Action. A type of firearm that is designed to operate in double action on the first shot, and in single action on the second and subsequent shots.

Caliber

The diameter of the bore of a firearm measured as a fraction of an inch. Although such a measurement may be frequently stated in millimeters. It is correctly expressed as ".40 caliber" (note the decimal point) or as "10 millimeter" (without "caliber" or the leading decimal point). Caliber numbers when used to identify the size of the bullet a gun will file are usually followed by words or letters to create the complete name of the cartridge. These letters often represent a brand name or an abbreviation for the name of the company that first introduced the round.

Gain Twist

A form of rifling where the helical angle (pitch) sharpens progressively down the bore in the interest of maximizing the bullets ultimate rotational speed by initiating it slowly.

Pattern

A shotgun term which refers to the manner in which the pellets spread out as they exit the gun. "The pattern" refers to the overall shape of the entire set. A tight pattern is one in which the pellets are closely grouped when they land on target. A loose pattern is one in which the pellets are widely spread.

Snap Cap

An inert ammunition-shaped object, used in practice to simulate misfeeds and other malfunctions. Some folks also use them during dry fire practice to cushion the firing pin as it strikes.

Internal Safety

A safety which is placed within the gun and is not accessible to the user. Internal safeties are generally designed to prevent unintentional discharges when the gun is dropped or mishandled.