Timing

The proper adjustment of the various interrelated moving parts of a gun so that every operation works in proper sequence, such as that the two ejectors of a double gun kick out the spent cases at the same instant and with the same force.

BUG

Abbreviation for 'Back Up Gun'

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.

WSM

Abbreviation for Winchester Short Magnum.

Sporterizing

The practice of modifying military-type firearms either to make them suitable for civilian sporting use. Common sporterizing includes changing the stock or sights.

Reactive Targets

Targets that do something when you hit them, such as fall over, burst, send up smoke, or make a noise.

Lede

The bevelled portion of the rifling at the rear end of the barrel (and the forward portion of the chamber) where the bullet first engages the lands.

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.

Fore-End

Also spelled Forend. That part of the stock forward of the action and located below the barrel or barrels. It is designed to give the shooter a place to hold the front end of the gun and protects the shooter's hand from getting burned on the hot barrel.

Ramrod

A long, slender, dowel-like tool used to force powder and shot down the bore of a muzzle-loading firearm. For hand-fired guns, normally retained in some kind of receptacle attached to the gun's barrel. Carried separately for muzzle-loading cannon.

Hand-Detachable Locks

The firing mechanism of a break-open gun which may be removed for inspection or cleaning without the use of tools. The release latch may be plainly visible or concealed. A feature typically seen on sidelock guns but also on the Westley Richards "droplock" boxlock action.

Frangible

A bullet that is designed to disintegrate into tiny particles upon impact to minimize their penetration for reasons of range safety, to limit environmental impact, or to limit the danger behind the intended target. Examples are the Glaser Safety Slug and the breaching round.

Scope Blocks

A pair of small dovetailed steel bases, screwed usually one to the barrel and one to the front receiver ring of a rifle, to accept mounts for target scopes such as the Unertl where the scope is allowed to move forward in the rings under the recoil of the rifle and which typically carry the windage and elevation adjustments in the mount.

Loading Gate

The hinged cover over the opening through which cartridges are inserted into the magazine.

Mauser Action

The premier bolt action, whose design by Paul Mauser coalesced in 1898, and from which were derived the Springfield 1903, the Winchester Model 70 and many others.

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.

VCCLEA

Violent Crime Control and Law Enforcement Act of 1994. It is an act of Congress dealing with crime and law enforcement that became law in 1994. Of the sections of the bill, it included the Federal Assault Weapons Ban.

Cape Gun

A two-barreled, side-by-side, shoulder-fired gun having one smoothbore shotgun barrel and one rifled barrel.

NAGR

The National Association for Gun Rights (NAGR) is a gun rights advocacy group in the United States. Headed by Dudley Brown, a long-time gun rights advocate, the National Association for Gun Rights was formed in 2000 as a grassroots, member-centric organization with a no-compromise approach to gun rights issues through an aggressive strategy.

Annulus

A tiny circular recess at the base of a cartridge case surrounding the primer pocket. Recoil from fired cartridges invariably impress a discernable ring on the breech or bolt face of a firearm, providing some evidence of the amount of use it has seen.