The Israel Defence Force adopted a heavy-barreled version of their standard Galil rifle as their squad automatic weapon and used it for several years, but in the late 1980s decided that a more purpose-built light machine gun would be preferable. One drawback of the heavy Galil was its fixed barrel, which made overheating, particularly in the Middle Eastern climate, an ever-present problem.
The Negev is a conventional enough weapon, using gas to drive a bolt carrier which contains a cam-operated rotating bolt. The bolt locks into a barrel extension, to which a quick-change barrel is attached by interrupted lugs. Thus, as soon as the barrel begins to overheat it can be rapidly changed for a fresh one, and the hot barrel allowed to cool. It also fires from an open bolt; the bolt is kept back by the trigger mechanism when the trigger is released so that air can flow through the barrel and into the interior of the receiver and thus assist in cooling between bursts of fire.
The feed system can deal with belts, Galil rifle magazines, M16 rifle magazines by means of a simple adapter, and even some form of drum feed. No adjustments have to be made when changing from one system to another, and there are safeguards to ensure that in the heat of battle, nobody tries to load from two sorts of feed at once.
The gas regulator has three positions; in normal conditions position one gives a rate of fire of 650-800 rounds per minute; position two gives a rate of 800-950 rounds per minute, or, in dusty or dirty conditions, can be used to give more power to overcome fouling. The third position shuts off the gas to the gas system in order to permit grenades to be launched from the muzzle.
The Negev can be used as a light machine gun or it can be fitted with a shorter (330 mm) barrel to act as an assault machine gun or rifle. The gun can be easily and quickly stripped into six sub-assemblies, including the bipod. All parts, including the quick-change barrels, are fully interchangeable, and the receiver is prepared for sight mounts to accept any kind of optical or electro-optical sight.
Technical specifications of Negev Light machine gun