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Sub-Machine Gun / Automatic Rifle

The most important innovation in firearm history is that of the invention of the machine gun. The scourge of World War I began an era of firearms that could fire non-stop until the trigger was released, or the ammunition to the firearm was expended. This began innovations which yielded the Soviet AK-47 in 1947, the M16 in 1963, and many types of machine guns which have gone from their bulky, crew-serviced size of WWI, to the light, accurate, single-operator weapons of the Gulf War.

The application of the automatic principle to the modern high-velocity small-arm of precision occupyied the attention of the small-arms experts of all armies and of numerous private inventors for many years. These numerous attempts were, in the case of the rifle, been largely doomed to failure because of the necessary limitations of space and weight. With an automatic rifle the work of extracting the empty cartridge-case, re-loading and re-cocking, is accomplished either by the motive power of the recoil or of the gas generated by the explosion of the powder, thus enabling a rapid and continuous fire to be maintained to the lull capacity of the weapons magazine.

Italy was the first country to adopt a sub-machine gun, the 'Villar Perosa' in 1915. The original production had no stock and was mounted in dual sets fired with thumb type triggers.

Although the USA was the third country to develop a sub-machine gun, this type of weapon was not adopted by the US until about 1928 when the US Marines used it at Nicaragua. The Thompson submachine gun or Tommy gun was invented by General John T. Thompson. It was the first hand held machine gun. Thompson was driven with the thought of creating a hand held machinegun that would help end the First World War, However, the first shipment of prototype guns destined for Europe arrived at the docks in New York city on 11 November 1918, the day the War ended. The 1928 Thompson sub-machine gun, the weapon of choice for both criminals and lawmen in 1920s Chicago. The widespread use of the Thompson was due mainly to the fact that it was the only allied submachine gun in mass production at the beginning of WWII.

The sub-machine gun, better known as the "grease gun," proved to be a favorite weapon in close combat. The compact size of the M3A1 Grease Gun, with 30 rround magazine, made it ideal for use inside tanks.

John Browning designed the BAR to provide an automatic rifle for use during World War I. The M1918 saw service toward the end of World War I. The M1918A2, adopted by the Army in 1940, saw extensive service during World War II and Korea. The BAR used .30-06 cal. cartridges in 20-round magazines. The BAR provided an effective rate of fire of 550 spm, and proved to be a very reliable weapon during adverse operating conditions.

When fielded in the mid-1980s, the Squad Automatic Weapon (SAW), or 5.56mm M249, was issued as a one-for-one replacement for the designated "automatic rifle" (M16A1) in the Fire Team. In this regard, the SAW filled the void created by the retirement of the Browning Automatic Rifle (BAR) during the 1950s because interim automatic weapons (e.g. M-14E2/M16A1) had failed as viable "base of fire" weapons. Early in the SAW's fielding, the Army identified the need for a Product Improvement Program (PIP) to enhance the weapon. This effort resulted in a "PIP kit" which modifies the barrel, handguard, stock, pistol grip, buffer, and sights.

Automatic riflemen use the direct-lay technique by aligning the sights of the weapon on the target. This is the easiest and quickest means of delivering fire.

Automatic riflemen use assault fire when in close combat. Assault fire involves firing without the aid of sights using the hip, shoulder, and underarm positions. The underarm position is best when rapid movement is required. In all three positions, automatic riflemen adjust their fire by observing the tracer and the impact of the bullets in the target area.

Defilade positions protect gunners from frontal or enfilading fires. Cover and concealment may not provide the gunner a view of some or all of the target area. In this instance, some other member of the platoon must observe the impact of the rounds and communicate adjustments to the gunner. Gunners and leaders must consider the complexity of laying on the target, the gunner's inability to make rapid adjustments to engage moving targets, the ease with which targets are masked, and the difficulty in achieving grazing fires for a final protective line.

The automatic rifleman's primary weapon is the M249 squad automatic weapon (SAW). Each infantry squad has two automatic weapons. The M249 provides the squad with a high volume of sustained long-range suppressive and lethal fires far beyond the range of the M16/M4 rifle. The automatic rifleman employs the SAW to suppress enemy infantry and bunkers, destroy enemy automatic rifle and antitank teams, and enable maneuver of other teams and squads.

The SAW is primarily a squad leader's weapon to use in the close fight as a light automatic weapon. The SAW provides the rifle squads with a light automatic weapon to take with them into the assault. These weapons fire from the bipod, from the hip, or from the underarm position. They target any enemy supporting weapons being fired from fixed positions anywhere on the squad's objective. When the enemy's supporting weapons have been destroyed, or if there are none, the SAW gunners distribute their fire over that portion of the objective that corresponds to their team's position. The SAW in the hands of a rifleman can provide mobility and a high volume of fire up front in the assault or across the squad's position in the defense. In the defense, the SAW adds the firepower of 10 or 20 riflemen without the addition of manpower. Characteristically, SAWs are light, fire rapidly, and they have more ammunition than the rifles in the squad they support. Under certain circumstances, the platoon leader may designate the SAW as a machine gun and, with some adjustments, use it as a platoon weapon.

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Page last modified: 07-07-2011 02:48:21 ZULU