UNLOAD

1. The complete removal of all ammunition from a firearm and it’s magazine 2. Disassembly of a cartridge or shell.

U-NOTCH SIGHT

A rear sight on pistols or revolvers having a flat top with a “U” shaped notch used with bead-topped front sight. Named after Ira Paine, 19th Century match and exhibition shooter. Also known as Paine Sight.

UNSERVICEABLE

A firearm which, for any reason, is no longer fit for firing.

UPSET FORGING

A gun barrel blank formed by hammering a steel bar to increase its diameter at one end for the purpose of providing a shank section.

VARIABLE CHOKE

An adjustable device attached to the muzzle of a shotgun in order to control the shot patterns.

VARMINT RIFLE

A sporting rifle with a heavy barrel, designed for long range small game hunting, firing high velocity, flat trajectory projectiles.

VELOCITY

The speed of a projectile at a given point along its trajectory.

VENTILATED CHOKE

A shotgun choke which is perforated for the release of propellant gases.

VENTILATED RIB

A raised sighting surface which is separated from the barrel by means of posts that allow air to circulate around it. Its purpose is to minimize heat waves in the line of sight. Also called Bridge Rib.

VERNIER SIGHT

A long-range sight with a mechanism for adjusting windage and/or elevation settings as read on a short scale in conjunction with graduations on a longer, linearly calibrated, scale.