Archives: Glossary

The abbreviation for Improved Military Rifle Powder. A single base, tubular, smokeless propellant.

A firearm is said to be “In Battery” when the breeching mechanism is in the proper position for firing.

A firearm design incorporating it’s firing mechanism substantially in line with the longitudinal axis of the barrel. Ignition gases are typically induced concentric to the bore with this design.

1. Usually a blank cartridge used in industrial applications such as stud drivers. Usually color coded to indicate power level. Also referred to as power tool cartridges and power actuated tool cartridges. 2. 8 Gauge industrial loads with single projectiles or buckshot used for cleaning continuous cement kilns and other industrial applications.

1. A device intended to function during recoil to set the fire control mechanism to fire a second barrel. 2. A device intended to function during recoil to prevent doubling on some double barrel shotguns.

A tool using impact to remove a bullet from a cartridge case.

A design in which the striker or hammer stops after hitting the firing-pin, requiring the firing-pin reach the primer under its own inertia.

A self-loading type firearm in which components of the locking system remains relatively stationary while the rest of the firearm recoils and thereafter unlocks the breech bolt to complete the cycle of extracting, ejecting and reloading.

The term used for firearms having two barrels and a single trigger wherein the inertia resulting from the recoil forces of firing one barrel causes the trigger sear to switch to the unfired barrel. A second pull of the trigger can then fire the second barrel.

A bullet having lubrication in grooves on the bearing surface of the projectile. When seated, these grooves are covered by the cartridge case.