KEEL

A spacer used to maintain center distance of double barrels during manufacture.

KEEPER

A means of holding straps or cords, such as gun slings, together with a loop or clip made of leather, metal or plastic.

KERNEL

A single particle of propellant powder.

KEYHOLE / KEYHOLING

An oblong or oval hole in a target that is produced by an unstable bullet striking the target at an angle to the bullet’s longitudinal axis.

KICKER

The part which draws back a rod which forces home a cartridge on some recoil operated firearms. Also refers to some break-open shotgun ejectors.

KINETIC ENERGY (FORMULA)

Based on the general equation for kinetic energy, Ek=½mv2, which directly uses mass (m) and velocity (v), the following formula is used to calculate the kinetic energy of a projectile (expressed in foot-pounds):

E=(W*V2)/(14000*gc).

In this formula, W = weight of projectile, in grains; V = velocity, in feet per second; gc= gravitational constant, 32.174 ft/s2

KNUCKLE

The front section of the action bar flats.

KNURL, KNURLING

1. A series of regular ridges or rectangles on a metal surface to help prevent slipping. Used on triggers, hammers, bolt handles, etc. 2. Sometimes used in referring to cartridge case or bullet cannelures.