Automatic rifle

2nd Lt. Val Browning with the Browning Automatic Rifle in France during World War I.

An automatic rifle is a type of magazine-fed rifle that uses either its recoil or a portion of the gas propelling the projectile to remove the spent cartridge case, cock the rifle, load a new cartridge and fire again repeatedly, as long as the trigger is held down or until the magazine is exhausted. Automatic rifles are distinguished from semi-automatic rifles in their ability to fire more than one shot in succession once the trigger is pulled. Many automatic rifles are select-fire weapons which are capable of firing in fully automatic and semi-automatic modes, or in some cases, even being capable of burst-fire.

History

The world's first automatic rifle was the Italian Cei-Rigotti. Introduced in 1900, these 6.5mm Carcano or 7.65×53mm gas-operated, selective-fire, carbines attracted considerable attention at the time. They used 10-, 20- and 50-round detachable box magazines. Unfortunately, they had several failings, including frequent jams and erratic shooting. In the end, no Army took an interest in the design and the rifle was abandoned before it could be further developed.

The Browning Automatic Rifle (BAR) was one of the first practical automatic rifles. The BAR made its successful combat debut in World War I and approximately 50,000 were made before the war came to an end. The BAR arose from the concept of "Walking Fire", an idea urged upon the Americans by the French who used the Chauchat light machine gun to fulfill that role. The BAR never entirely lived up to the designers hopes; being neither a rifle nor a machinegun. "For its day, though, it was a brilliant design produced in record time by John Browning, and it was bought and used by many countries around the world. It was the standard squad light automatic of the U.S. infantry during World War II and saw use in every theater of war." "The US forces abandoned the BAR in the middle 1950s, though it was retained in reserve stocks for several years; it survived in smaller countries until the late 1970s."

The FG 42 was a selective fire automatic rifle produced in Germany during World War II. The weapon was developed specifically for the use of the Fallschirmjäger airborne infantry in 1942 and was used in limited numbers until the end of the war. It served as a squad automatic rifle in much the same role as the Browning BAR. It was considered one of the most advanced weapon designs of World War II, the FG 42 influenced post-war small arms development and most of its design was copied by the US Army when they developed the M60 GPMG.

The Germans were the first to pioneer the assault rifle concept, during World War II, based upon research that showed that most firefights happen within 400 meters and that contemporary rifles were over-powered for most small arms combat. The Germans sought to develop a select-fire intermediate powered rifle combining the firepower of a submachine gun with the accuracy and range of a rifle. This was done by shortening the standard 7.92×57mm cartridge to 7.92×33mm and giving it a lighter 125-grain bullet, that limited range but allowed for more controllable automatic fire. The result was the Sturmgewehr 44.

Like the Germans, the Soviets were influenced by experience showing most combat happens within 400 meters and that their soldiers were consistently outgunned by heavily armed German troops, especially those armed with the Sturmgewehr 44 assault rifles. The Soviets were so impressed with the Sturmgewehr 44, that after World War II, they held a design competition to develop an assault rifle of their own. The winner was the AK-47. It was finalized, adopted and entered widespread service in the Soviet army in the early 1950s. Its firepower, ease of use, low production costs, and reliability was perfectly suited for the Red Army's new mobile warfare doctrines. The AK-47 was widely supplied or sold to nations allied with the USSR and the blueprints were shared with several friendly nations (the People's Republic of China standing out among these with the Type 56).

The U.S. Army was influenced by combat experience with semi-automatic weapons such as the M1 Garand and M1 carbine, which enjoyed a significant advantage over enemies armed primarily with bolt-action rifles. Although U.S. Army studies of World War II combat accounts had very similar results to that of the Germans and Soviets, the U.S. Army maintained its traditional views and preference for high-powered semi-automatic rifles.

After World War II, the United States military started looking for a single automatic rifle to replace the M1 Garand, M1/M2 Carbines, M1918 Browning Automatic Rifle, M3 "Grease Gun" and Thompson submachine gun. However, early experiments with select-fire versions of the M1 Garand proved disappointing. During the Korean War, the select-fire M2 Carbine largely replaced submachine guns in US service. Although, combat experience suggested that the .30 Carbine round was underpowered. American weapons designers reached the same conclusion as the Germans and Soviets: an intermediate round was necessary, and recommended a small caliber, high velocity cartridge.

However, senior American commanders having faced fanatical enemies and experienced major logistical problems during WWII and the Korean War, insisted that a single powerful .30 caliber cartridge be developed, that could not only be used by the new automatic rifle, but by the new general purpose machine gun (GPMG) in concurrent development. This culminated in the development of the 7.62×51mm NATO cartridge and the M14 rifle which was basically an improved select-fire M1 Garand with a 20-round magazine. The U.S. also adopted the M60 GPMG. Its NATO partners adopted the FN FAL and HK G3 rifles, as well as the FN MAG and Rheinmetall MG3 GPMGs.

The FN FAL is a 7.62×51mm NATO, selective fire, automatic rifle produced by the Belgian armaments manufacturer Fabrique Nationale de Herstal (FN). During the Cold War it was adopted by many North Atlantic Treaty Organization (NATO) countries, most notably with the British Commonwealth as the L1A1. It is one of the most widely used rifles in history, having been used by more than 90 countries. The FAL was predominantly chambered for the 7.62mm NATO round, and because of its prevalence and widespread use among the armed forces of many western nations during the Cold War it was nicknamed "The right arm of the Free World".

The H&K G3 is a 7.62×51mm NATO, selective fire, automatic rifle produced by the German armament manufacturer Heckler & Koch GmbH (H&K) in collaboration with the Spanish state-owned design and development agency CETME (Centro de Estudios Técnicos de Materiales Especiales). The rifle proved successful in the export market, being adopted by the armed forces of over 60 countries. After WWII, German technicians involved in developing the Sturmgewehr 45, continued their research in France at CEAM. The StG45 mechanism was modified by Ludwig Vorgrimler and Theodor Löffler at the Mulhouse facility between 1946 and 1949. Vorgrimler later went to work at CETME in Spain and developed the line of CETME automatic rifles based on his improved Stg45 design. Germany eventually purchased the license for the CETME design and manufactured the Heckler & Koch G3 as well as an entire line of weapons built on the same system, one of the most famous being the MP5 SMG.

The first confrontations between the AK-47 and the M14 (assault rifle vs battle rifle) came in the early part of the Vietnam War. Battlefield reports indicated that the M14 was uncontrollable in full-auto and that soldiers could not carry enough ammo to maintain fire superiority over the AK-47. A replacement was needed: A medium between the traditional preference for high-powered rifles such as the M14, and the lightweight firepower of the M2 Carbine.

As a result, the Army was forced to reconsider a 1957 request by General Willard G. Wyman, commander of the U.S. Continental Army Command (CONARC) to develop a .223 caliber (5.56 mm) select-fire rifle weighing 6 lbs (2.7 kg) when loaded with a 20-round magazine. The 5.56mm round had to penetrate a standard U.S. helmet at 500 yards (460 meters) and retain a velocity in excess of the speed of sound, while matching or exceeding the wounding ability of the .30 Carbine cartridge.

This request ultimately resulted in the development of a scaled-down version of the Armalite AR-10, called AR-15 rifle. However, despite overwhelming evidence that the AR-15 could bring more firepower to bear than the M14, the Army opposed the adoption of the new rifle. In January 1963, Secretary of Defense Robert McNamara concluded that the AR-15 was the superior weapon system and ordered a halt to M14 production. At the time, the AR-15 was the only rifle available that could fulfill the requirement of a universal infantry weapon for issue to all services. After modifications (Most notably: the charging handle was re-located from under the carrying handle like AR-10 to the rear of the receiver), the new redesigned rifle was subsequently adopted as the M16.

In March 1970, the U.S. recommended that all NATO forces adopt the 5.56×45mm cartridge. This shift represented a change in the philosophy of the military's long-held position about caliber size. By the middle of the 1970s, other armies were looking at assault rifle type weapons. A NATO standardization effort soon started and tests of various rounds were carried out starting in 1977. The U.S. offered the 5.56×45mm M193 round, but there were concerns about its penetration in the face of the wider introduction of body armor. In the end the Belgian 5.56×45mm SS109 round was chosen (STANAG 4172) in October 1980. The SS109 round was based on the U.S. cartridge but included a new stronger, heavier, 62 grain bullet design, with better long range performance and improved penetration (specifically, to consistently penetrate the side of a steel helmet at 600 meters).

During the 1970s, the USSR developed the AK-74 and the 5.45×39mm cartridge, which has similar physical characteristics to the U.S. 5.56×45mm cartridge. Also during the 1970s, Finland, Israel, South Africa and Sweden introduced AK type rifles in 5.56×45mm. During the 1990s, the Russians developed the AK-101 in 5.56×45mm NATO for the world export market. In addition, Bulgaria, Czechoslovakia, Hungary, Poland and former countries of Yugoslavia have also rechambered their locally produced AK variants to 5.56mm NATO. The adoption these cartridges cemented the world-wide trend toward small caliber, high velocity cartridges.

In 1977, Austria introduced the 5.56×45mm Steyr AUG bullpup rifle, often cited as the first successful bullpup rifle, finding service with the armed forces of over twenty countries. It was highly advanced for the 1970s, combining in the same weapon the bullpup configuration, a polymer housing, dual vertical grips, an optical sight as standard, and a modular design. Highly reliable, light, and accurate, the Steyr AUG showed clearly the potential of the bullpup layout. In 1978, France introduced the 5.56×45mm FAMAS bullpup rifle. In 1985, the British introduced the 5.56×45mm L85 bullpup rifle. In the late 1990s, Israel introduced the Tavor TAR-21 and China's People's Liberation Army's (the world's largest army) adopted QBZ-95. By the turn of the century, the bullpup design had achieved world-wide acceptance.

Gallery

• 
  M1918A2 Browning Automatic Rifle
• 
  Both early (top) and late-war (bottom) variants of the FG 42.
• 
  The German StG 44, the first assault rifle manufactured in significant numbers
• 
  An AK-47 with machined receiver
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  M1 Garand Rifle and M1 Carbine
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  U.S. M14 rifle, advanced by the proponents of the battle rifle concept
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  British L1A1 (FN FAL)
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  Norwegian AG-3 (HK G3)
• 
  American 5.56×45mm M16A1
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  Russian 5.45×39mm AK-74M rifle
• 
  The Steyr AUG was one of the first bullpup rifles to enter widespread use.
• 
  FAMAS G2 with bayonet
• 
  British SA-80 (L85A1) rifle in 1996.
• 
  Israeli Tavor 21
• 
  China's People's Liberation Army's QBZ-95
• Turkish 7.62×51mm MPT-76 battle rifle
  Turkish 7.62×51mm MPT-76 battle rifle

See also

• Semi-automatic rifle
• Assault rifle
• Battle rifle
• Marksman rifle
• Sniper rifle
• Light machine gun
• Squad automatic weapon
• List of firearms