LUMP

One of several projections located on the underside of the barrel or barrels on break action guns, which serves to secure the barrels to the action or receiver. See Barrel Lug.

LOADING GATE

1. Revolvers: A hinged piece attached to the frame which is opened to permit loading. 2. Shoulder Arms: A spring loaded cover for the loading port.

LOW CUP

Correct term for shotshells having a low metal head type of construction.

LOADING PORT

The opening in a receiver where a cartridge may be placed in the firearm either directly into the chamber or the magazine.

LOADING RAMP

A platform or cut placed in the bottom of the receiver that aids in guiding a cartridge into the chamber as the action is closed.

LUBRICATION GROVE

A circumferential groove in a projectile for the purpose of holding lubrication.

LOCK

1. A general term referring to the total firing mechanism in a firearm. 2. Range command sometimes used to indicate engagement of a manual safety (“Lock your firearms”). 3. An accessory intended to help secure a firearm from unauthorized use.

LOCK ENERGY

The amount of energy delivered to the primer from the firing-pin blow.