La France M16K - Design

Design

The M16K is a so-called "K" weapon ("K" standing for the German word Kurz meaning short.) The La France M16K, was basically a standard military M16 rifle, chambered for the standard issue 5.56 mm cartridge with an 8 3/8 inch (213 mm) barrel. The standard barrel length is 20 inches (508 mm). Like many automatic and semi-automatic weapons the M16 utilizes pressure from the propellant gases in the barrel to cycle the bolt of the firearm. Most automatic weapons use a mechanical device such as a rod and piston between the bolt and the propellant gases. This is not the case in the M16 design in which gases are tapped off the barrel near the muzzle and flow though a tube to directly impinge on the bolt to initiate the auto loading cycle. In a standard issue M16, the gas tube is roughly 16 inches (406 mm) long to produce an automatic (cyclic) rate of fire of approximately 650 rounds per minute. Shortening the barrel increases the rate of fire significantly and thereby makes the weapon difficult to control and less reliable. To use a significantly shorter barrel than the standard issue without increasing the rate of fire, La France designed (and subsequently patented) an adjustable gas system that would keep the rate of fire the same as with a full-length barrel.