Project Abakan was a Soviet /Russian advanced assault rifle program in rival to the US Advanced Combat Rifle that took place between 1980 and 1994.
130-485: The 1960s ushered a new generation of assault rifles with the introduction of smaller calibers. U.S. military analysis of combat during the Second World War showed that a greater volume of fire at shorter ranges was more significant than long range accuracy. They decided that a smaller caliber would be more effective in most conditions, because the soldier could carry more ammunition. In 1963, United States adopted
260-576: A detachable magazine . Assault rifles were first put into mass production and accepted into widespread service during World War II. The first assault rifle to see major usage was the German StG 44 , a development of the earlier Mkb 42 . While immediately after World War II, NATO countries were equipped with battle rifles , the development of the M16 rifle during the Vietnam War prompted
390-578: A "manual bolt closure," allowing a soldier to ram in a round if it failed to seat properly. The Air Force, which was buying the rifle, and the Marine Corps, which had tested it both objected to this addition, with the Air Force noting, "During three years of testing and operation of the AR-15 rifle under all types of conditions the Air Force has no record of malfunctions that could have been corrected by
520-649: A 20-round magazine. In 1964, the XM16E1 entered US military service as the M16 and in the following year was deployed for jungle warfare operations during the Vietnam War . In 1969, the M16A1 replaced the M14 rifle to become the US military's standard service rifle. The M16A1 incorporated numerous modifications including a bolt-assist, chrome-plated bore, protective reinforcement around
650-562: A 20-round magazine. The 5.56 mm round had to penetrate a standard U.S. helmet at 460 metres (500 yd) 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 the ArmaLite AR-15 rifle. However, despite overwhelming evidence that
780-400: A 30-round detachable box magazine. This weapon was the prototype of all successful automatic rifles. Characteristically (and unlike previous rifles) it had a straight stock with the barrel under the gas cylinder to reduce the turning moment of recoil of the rifle in the shoulder and thus help reduce the tendency of shots to climb in automatic fire. The barrel and overall length were shorter than
910-469: A 30-round magazine, because of the adoption of a thicker barrel profile. The thicker barrel is more resistant to damage when handled roughly and is also slower to overheat during sustained fire. Unlike a traditional "bull" barrel that is thick its entire length, the M16A2's barrel is only thick forward of the handguards. The barrel profile under the handguards remained the same as the M16A1 for compatibility with
1040-652: A Sturmgewehr was demonstrated before the People's Commissariat of Arms of the USSR . The Soviets were so impressed with the Sturmgewehr that they immediately set about developing an intermediate caliber automatic rifle of their own to replace the badly outdated Mosin–Nagant bolt-action rifles and PPSh-41 submachine guns that armed most of the Red Army. The Soviets soon developed the 7.62×39mm M43 cartridge, which
1170-533: A comic book-style operations manual. As a result, reliability problems were largely resolved and the M16A1 rifle achieved widespread acceptance by U.S. troops in Vietnam. In 1969, the M16A1 officially replaced the M14 rifle to become the U.S. military's standard service rifle . In 1970, the new WC 844 powder was introduced to reduce fouling. Colt, H&R, and GM Hydramatic Division manufactured M16A1 rifles during
1300-554: A jam when his M16 was covered in mud after climbing out of a canal. The weapon was cleared and resumed firing with the next chambered round. Furthermore, the Marine Chief Warrant Officer responsible for weapons training and performance of the Third Battalion, Sixth Marines, reported that "We've had nil in the way of problems; we've had no issues", with his battalion 's 350 M16s and 700 M4s. The M16
1430-592: A large flash suppressor had to be fitted". "Nevertheless, as a short-range weapon it is quite adequate and thus, [despite] its caliber, [the Colt Commando ] is classed as a submachine gun." Other compact assault rifles, such as the HK53 , AKS-74U and the Daewoo K1 , have been made and they have also been called submachine guns. In 1977, Austria introduced the 5.56×45mm Steyr AUG bullpup rifle, often cited as
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#17327980052641560-436: A level of soldier confidence their weapon will not break or need repair. Both factors were attributed to high levels of soldiers performing their maintenance. 60 percent of M16 users offered recommendations for improvements. Requests included greater bullet lethality, newly built instead of rebuilt rifles, better-quality magazines, decreased weight, and a collapsible stock. Some users recommended shorter and lighter weapons such as
1690-579: A manual bolt closing device." They also noted that the closure added weight and complexity, reducing the reliability of the weapon. Colonel Harold Yount, who managed the Army procurement, would later state the bolt closure was added after direction from senior leadership, rather than as a result of any complaint or test result, and testified about the reasons: "the M-1, the M-14, and the carbine had always had something for
1820-438: A misapplication of the term. The 1890s Cei-Rigotti prototype was built to fire the fully powered 7.65×53mm Mauser and the weaker 6.5×52mm Carcano , it was somewhat of a predecessor. However, it had its magazine fixed. The Fedorov Avtomat (also anglicized as Federov, Russian: Автома́т Фёдорова , romanized : Avtomát Fyódorova , IPA: [ɐftɐˈmat ˈfʲɵdərəvə] , lit. 'Fyodorov's automatic rifle')
1950-463: A modular design with a wide range of accessories (telescoping butt-stocks, optics, bi-pods, etc.) that could be easily removed and arranged in a variety of configurations. The adoption of the M16, the H&;K33, and the 5.56×45mm cartridge inspired an international trend towards relatively small-sized, lightweight, high-velocity military service cartridges that allow a soldier to carry more ammunition for
2080-496: A rear sight that could be set for specific range settings and also served to protect the charging handle. The M16 carry handle also provided mounting groove interfaces and a hole at the bottom of the handle groove for mounting a Colt 3×20 telescopic sight featuring a Bullet Drop Compensation elevation adjustment knob for ranges from 100 to 500 yd (91 to 457 m). This concurs with the pre-M16A2 maximum effective range of 460 m (503 yd). The Colt 3×20 telescopic sight
2210-510: A rifle with a one turn in 7 in (1:177.8 mm or 32 calibers) twist barrel. NATO SS109 ball and L110 tracer bullets should only be used in emergency situations at ranges under 90 m (98 yd) with a one turn in 12 inches (1:304.8 mm or 54.8 calibers) twist, as this twist is insufficient to stabilize these projectiles. Weapons designed to adequately stabilize both the M193 or SS109 projectiles (like civilian market clones) usually have
2340-419: A select-fire intermediate powered rifle combining the firepower of a submachine gun with the range and accuracy of a rifle. The result was the Sturmgewehr 44, an improvement of the earlier Maschinenkarabiner 42(H) , and approximately half a million Sturmgewehrs were produced by the war's end. It fired a new and revolutionary intermediate powered cartridge, the 7.92×33mm Kurz. This new cartridge
2470-478: 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 failed to recognize the importance of the assault rifle concept, and instead maintained its traditional views and preference for high-powered semi-automatic rifles. At the time, the U.S. Army believed that
2600-404: A six-groove, right-hand twist, one turn in 9 inches (1:228.6 mm or 41.1 calibers) or one turn in 8 inches (1:203.2 mm or 36.5 calibers) bore, although other and 1:7 inches twist rates are available as well. The (M16's) Stoner system provides a very symmetric design that allows straight-line movement of the operating components. This allows recoil forces to drive straight to
2730-470: A small-caliber, high-velocity cartridge. Senior American commanders had faced fanatical enemies and experienced major logistical problems during World War II and the Korean War, and insisted that a single powerful .30 caliber cartridge be developed, that could be used by the new automatic rifle, and also by the new general-purpose machine gun (GPMG) in concurrent development. This culminated in
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#17327980052642860-533: A stoppage, while 80 percent of those that experienced a stoppage said it had little impact on their ability to clear the stoppage and re-engage their target. Half of the M16 users experienced failures in their magazines to feed. 83 percent (986 troops) did not need their rifles repaired while in the theater. 71 percent (843 troops) were confident in the M16's reliability, defined as a level of soldier confidence their weapon will fire without malfunction, and 72 percent (855 troops) were confident in its durability, defined as
2990-684: A traditional rifle and it had a pistol grip to hold the weapon more securely in automatic fire. "The principle of this weapon—the reduction of muzzle impulse to get usable automatic fire within the actual ranges of combat—was probably the most important advance in small arms since the invention of smokeless powder ." Like the Germans, the Soviets were influenced by experience showing that most combat engagements occur within 400 metres (1,300 ft) and that their soldiers were consistently outgunned by heavily armed German troops, especially those armed with Sturmgewehr 44 assault rifles. On July 15, 1943,
3120-534: A velocity over 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 , named the ArmaLite AR-15 . The AR-15 was first revealed by Eugene Stoner at Fort Benning in May 1957. The AR-15 used .22-caliber bullets, which destabilized when they hit a human body, as opposed to
3250-414: A windage drum that can be adjusted during zeroing with about 1 MOA increments. The front sight is a tapered round post of approximately 0.0625 in (1.59 mm) diameter adjustable during zeroing in about 1 MOA increments. A cartridge or tool is required to (re)zero the sight line. Assault rifle An assault rifle is a select fire rifle that uses an intermediate-rifle cartridge and
3380-597: Is a 5.56×45mm assault rifle, designed in the early 1990s by Heckler & Koch in Germany as a replacement for the heavier G3. It was accepted into service with the Bundeswehr in 1997, replacing the G3. The G36 is gas-operated and feeds from a 30-round detachable box magazine or 100-round C-Mag drum magazine . The G36 was made with the extensive use of lightweight, corrosion-resistant synthetic materials in its design;
3510-594: Is a 7.62×51mm, 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 semi-automatic L1A1 . It is one of the most widely used rifles in history, having been used by more than 90 countries. The FAL
3640-442: Is a lightweight, 5.56 mm, air-cooled, gas-operated , magazine -fed assault rifle , with a rotating bolt . The M16's receivers are made of 7075 aluminum alloy , its barrel, bolt, and bolt carrier of steel, and its handguards, pistol grip, and buttstock of plastics. The M16 internal piston action was derived from the original ArmaLite AR-10 and ArmaLite AR-15 actions. This internal piston action system designed by Eugene Stoner
3770-669: Is a select-fire infantry rifle and also one of the world's first operational automatic rifles, designed by Vladimir Grigoryevich Fyodorov in 1915 and produced in the Russian Empire and later in the Russian Soviet Federative Socialist Republic . A total of 3,200 Fedorov rifles were manufactured between 1915 and 1924 in the city of Kovrov ; the vast majority of them were made after 1920. The weapon saw limited combat in World War I , but
3900-404: Is commonly called a direct impingement system, but it does not use a conventional direct impingement system. In U.S. patent 2,951,424 , the designer states: ″This invention is a true expanding gas system instead of the conventional impinging gas system.″ The gas system, bolt carrier, and bolt-locking design is ammunition specific, since it does not have an adjustable gas port or valve to adjust
4030-411: Is lighter and more compact than a gas-piston design. However, this design requires that combustion byproducts from the discharged cartridge be blown into the receiver as well. This accumulating carbon and vaporized metal build-up within the receiver and bolt carrier negatively affects reliability and necessitates more intensive maintenance on the part of the individual soldier. The channeling of gasses into
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4160-403: Is that which would be measured if the rifle were fired suspended from strings, free to recoil. A rifle's perceived recoil is also dependent on many other factors which are not readily quantified. The M16's most distinctive ergonomic feature is the carrying handle and rear sight assembly on top of the receiver. This is a by-product of the original AR-10 design, where the carrying handle contained
4290-426: Is the piston sleeve. While the M16 is commonly said to use a direct impingement system, this is wrong, and it is instead correct to say it uses an internal piston system. This system is however ammunition specific, since it does not have an adjustable gas port or valve to adjust the weapon to various propellant and projectile or barrel length specific pressure behavior. The M16 operating system designed by Stoner
4420-530: The 5.56×45 mm NATO cartridge has become not only the NATO standard but "the standard assault-rifle cartridge in much of the world." It also led to the development of small-caliber high-velocity service rifles by every major army in the world. It is a benchmark against which other assault rifles are judged. In July 1960, General Curtis LeMay was impressed by a demonstration of the ArmaLite AR-15. In
4550-528: The Advanced Research Projects Agency , sent 10 AR-15s to South Vietnam. The reception was enthusiastic, and in 1962 another 1,000 AR-15s were sent. United States Army Special Forces personnel filed battlefield reports lavishly praising the AR-15 and the stopping power of the 5.56 mm cartridge, and pressed for its adoption. The damage caused by the 5.56 mm bullet was originally believed to be caused by "tumbling" due to
4680-506: The Army of the Republic of Vietnam (ARVN). The South Vietnam soldiers issued glowing reports of the weapon's reliability, recording zero broken parts while firing 80,000 rounds in one stage of testing, and requiring only two replacement parts for the 1,000 weapons over the entire course of testing. The report of the experiment recommended that the U.S. provide the AR-15 as the standard rifle of
4810-518: 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 7.62×51 mm NATO cartridge. The U.S. Army then began testing several rifles to replace the obsolete M1. Springfield Armory's T44E4 and heavier T44E5 were essentially updated versions of
4940-508: The Korean War , the select-fire M2 carbine largely replaced the submachine gun in US service and became the most widely used carbine variant. However, combat experience suggested that the .30 carbine round was underpowered. American weapons designers concluded that 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 World War II and
5070-713: The M16 rifle and the smaller 5.56×45mm cartridge to replace the M14 Rifle and larger 7.62×51mm . In 1980, NATO adopted the 5.56mm as the standard-issue rifle cartridge. In 1974, the Soviet Army also replaced the AKM with the AK-74 assault rifle chambered for the new smaller 5.45×39mm caliber. In spite of the smaller caliber and many other improvements the AK-74 failed to overcome the major shortcoming of its predecessor, which
5200-464: The M203 grenade launcher . Early model M16 barrels had a rifling twist of four grooves, right-hand twist , one turn in 14 inches (1:355.6 mm or 64 calibers) bore—as it was the same rifling as used by the .222 Remington sporting cartridge. After finding out that under unfavorable conditions, military bullets could yaw in flight at long ranges, the rifling was soon altered. Later M16 models and
5330-771: The M4 carbine . Some issues have been addressed with the issuing of the Improved STANAG magazine in March 2009, and the M855A1 Enhanced Performance Round in June 2010. In early 2010, two journalists from The New York Times spent three months with soldiers and Marines in Afghanistan. While there, they questioned around 100 infantry troops about the reliability of their M16 rifles, as well as
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5460-572: The Type 56 ). As a result, more AK-type weapons have been produced than all other assault rifles combined. As of 2004, "of the estimated 500 million firearms worldwide, approximately 100 million belong to the Kalashnikov family, three-quarters of which are AK-47s." The U.S. Army was influenced by combat experience with semi-automatic weapons such as the M1 Garand and M1 Carbine , which enjoyed
5590-571: The U.S. Special Forces asked and was given permission, to make the AR-15 its standard weapon. Other users included Army Airborne units in Vietnam and some units affiliated with the Central Intelligence Agency . As more units adopted the AR-15, Secretary of the Army Cyrus Vance ordered an investigation into why the weapon had been rejected by the Army. The resulting report found that Army Materiel Command had rigged
5720-474: The Washington Daily News broke the story. Eventually, the M16 became the target of a congressional investigation. The investigation found that: When these issues were addressed and corrected by the M16A1, the reliability problems decreased greatly. According to a 1968 Department of Army report, the M16A1 rifle achieved widespread acceptance by U.S. troops in Vietnam. "Most men armed with
5850-499: The .30 round, which typically passed through in a straight line. The smaller caliber meant that it could be controlled in autofire due to the reduced bolt thrust and free recoil impulse. Being almost one-third the weight of the .30 meant that the soldier could sustain fire for longer with the same load. Due to design innovations, the AR-15 could fire 600 to 700 rounds a minute with an extremely low jamming rate. Parts were stamped out, not hand-machined, so they could be mass-produced, and
5980-520: The 1960s other countries would follow the Americans' lead and begin to develop 5.56×45mm assault rifles, most notably Germany with the Heckler & Koch HK33 . The HK33 was essentially a smaller 5.56mm version of the 7.62×51mm Heckler & Koch G3 rifle. As one of the first 5.56mm assault rifles on the market, it would go on to become one of the most widely distributed assault rifles. The HK33 featured
6110-508: The 1970s, Finland, Israel, and South Africa introduced AK type assault rifles in 5.56×45mm. Sweden began the transition with trails in 1981 and full adaptation in 1986. During the 1990s, Russia developed the AK-101 in 5.56×45mm NATO for the world export market. In addition, Bulgaria, Czechoslovakia, Hungary, Poland and Yugoslavia (i.e., Serbia) have also rechambered their locally produced assault rifles to 5.56mm NATO. The AK-74 assault rifle
6240-543: 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 5.56mm NATO Tavor TAR-21 . In 1997, China adopted the QBZ-95 in the new 5.8×42mm cartridge, which they claim is superior to both the 5.56×45mm and the 5.45×39mm. By the turn of the century, the bullpup assault rifle design had achieved worldwide acceptance. The Heckler & Koch G36
6370-416: The 5.56×45mm NATO cartridge has become not only the NATO standard but "the standard assault-rifle cartridge in much of the world". It also led to the development of small-caliber high-velocity service rifles by every major army in the world, including the USSR and People's Republic of China. Today, many small arms experts consider the M16 the standard by which all other assault rifles are judged. During
6500-416: 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
6630-519: 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 ammunition to maintain fire superiority over the AK-47. And, while the M2 Carbine offered a high rate of fire, it was under-powered and ultimately outclassed by the AK-47. A replacement
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#17327980052646760-559: The AK-47, the [M1] carbine or a pistol." In March 1970, the "President's Blue Ribbon Defense Panel" concluded that the issuance of the M16 saved the lives of 20,000 U.S. servicemen during the Vietnam War, who would have otherwise died had the M14 remained in service. However, the M16 rifle's reputation has suffered as of 2011. Another underlying cause of the M16's jamming problem was identified by ordnance staff that discovered that Stoner and ammunition manufacturers had initially tested
6890-444: 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,
7020-498: The AR-15 using DuPont IMR8208M extruded (stick) powder. Later ammunition manufacturers adopted the more readily available Olin Mathieson WC846 ball powder. The ball powder produced a longer peak chamber pressure with undesired timing effects. Upon firing, the cartridge case expands and seals the chamber ( obturation ). When the peak pressure starts to drop the cartridge case contracts and then can be extracted. With ball powder,
7150-536: The AR-15 was the superior weapon system and ordered a halt to M14 production. In late 1963, the Defense Department began mass procurement of rifles for the Air Force and special Army units. Secretary McNamara designated the Army as the procurer for the weapon with the Department, which allowed the Army ordnance establishment to modify the weapon as they wished. The first modification was the addition of
7280-613: The ARVN, but Admiral Harry Felt , then Commander in Chief of Pacific Forces, rejected the recommendations on the advice of the U.S. Army. Throughout 1962 and 1963, the U.S. military extensively tested the AR-15. Positive evaluations emphasized its lightness, "lethality", and reliability. However, the Army Materiel Command criticized its inaccuracy at longer ranges and lack of penetrating power at higher ranges. In early 1963,
7410-710: The Armory. In the end, the U.S. Army chose the T44, now named the M14 rifle , which was an improved M1 Garand with a 20-round magazine and automatic fire capability. The U.S. also adopted the M60 general-purpose machine gun (GPMG). Its NATO partners adopted the FN FAL and HK G3 rifles, as well as the FN MAG and Rheinmetall MG3 GPMGs. The first confrontations between the AK-47 and
7540-594: The Army and Colt worked to make modifications to the M4s and M16A4s to address the problems found. In tests conducted in 2005 and 2006 the Army found that on average, the new M4s and M16s fired approximately 5,000 rounds between stoppages. In December 2006, the Center for Naval Analyses (CNA) released a report on U.S. small arms in combat. The CNA conducted surveys on 2,608 troops returning from combat in Iraq and Afghanistan over
7670-506: The Army, Cyrus Vance, to test the M14, the AR-15, and the AK-47. The Army reported that only the M14 was suitable for service, but Vance wondered about the impartiality of those conducting the tests. He ordered the Army Inspector General to investigate the testing methods used; the inspector general confirmed that the testers were biased toward the M14. In January 1963, Secretary McNamara received reports that M14 production
7800-842: The Commission of the Council of Ministers of the USSR in the military-industrial issued Required Operational Capability (ROC) number 280 27.08.81. Because of the expensive and time-consuming nature of manufacturing and adopting a new assault rifle this ROC specified that any new assault rifle had to be 1.5 to 2.0 times more "combat effective" than the AK-74. The complexity of modern firearms design and manufacturing dictated that design bureaus with dedicated manufacturing facilities were enlisted to design and manufacture prototypes. The prototypes were produced after three years by TsKIB SOO (subsidiary of KBP Instrument Design Bureau ), Kovrovskiy mechanical and Izhmash (Izhevsk Mechanical Works) plants under
7930-690: The German word Sturmgewehr (which translates to "assault rifle") as the new name for the MP 43 ( Maschinenpistole ) , subsequently known as the Sturmgewehr 44 . Allied propaganda suggested that the name was chosen for propaganda purposes, but the main purpose was to differentiate the Sturmgewehr from German submachine guns such as the MP 40 . It has been suggested, however, that the Heereswaffenamt
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#17327980052648060-407: The M1 Garand proved disappointing. During the Korean War , the select-fire M2 Carbine largely replaced the submachine gun in U.S. service and became the most widely used Carbine variant. Combat experience suggested that the .30 Carbine round was under-powered. American weapons designers reached the same conclusion as the German and Soviet ones: an intermediate round was necessary, and recommended
8190-613: The M1 chambered for the new 7.62 mm round, while Fabrique Nationale submitted their FN FAL as the T48 . ArmaLite entered the competition late, hurriedly submitting several AR-10 prototype rifles in the fall of 1956 to the U.S. Army's Springfield Armory for testing. The AR-10 featured an innovative straight-line barrel/stock design, forged aluminum alloy receivers, and with phenolic composite stocks. It had rugged elevated sights, an oversized aluminum flash suppressor and recoil compensator , and an adjustable gas system. The final prototype featured an upper and lower receiver with
8320-444: The M14 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 ammunition to maintain fire superiority over the AK-47. And, while the M2 carbine offered a high rate of fire, it was under-powered and ultimately outclassed by the AK-47. A replacement was needed: a medium between the traditional preference for high-powered rifles such as
8450-445: 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-inch caliber (5.56 mm) select-fire rifle weighing 6 lb (2.7 kg) when loaded with a 20-round magazine. The 5.56 mm round had to penetrate a standard U.S. helmet at 500 yards (460 meters) and retain
8580-474: The M14. However, advocates for the AR-15 gained the attention of Air Force Chief of Staff General Curtis LeMay . After testing the AR-15 with the ammunition manufactured by Remington that Armalite and Colt recommended, the Air Force declared that the AR-15 was its 'standard model' and ordered 8,500 rifles and 8.5 million rounds. Advocates for the AR-15 in the Defense Advanced Research Projects Agency acquired 1,000 Air Force AR-15s and shipped them to be tested by
8710-413: The M16 in Vietnam rated this rifle's performance high, however, many men entertained some misgivings about the M16's reliability. When asked what weapon they preferred to carry in combat, 85 percent indicated that they wanted either the M16 or its [smaller] carbine-length version, the XM177E2 ." Also, "the M14 was preferred by 15 percent, while less than one percent wished to carry either the Stoner rifle ,
8840-531: The M16 in frontline combat units with a shorter and lighter version, the M4 carbine . In April 2022, the U.S. Army selected the SIG MCX SPEAR as the winner of the Next Generation Squad Weapon Program to replace the M16/M4. The new rifle is designated XM7 . In 1928, a U.S. Army 'Caliber Board' conducted firing tests at Aberdeen Proving Ground and recommended transitioning to smaller caliber rounds, mentioning, in particular .27 in (6.86 mm) caliber. Largely in deference to tradition, this recommendation
8970-487: The M16A1 had an improved rifling with six grooves, right-hand twist, one turn in 12 inches (1:304.8 mm or 54.8 calibers) for increased accuracy and was optimized to adequately stabilize the M193 ball and M196 tracer bullets. M16A2 and current models are optimized for firing the heavier NATO SS109 ball and long L110 tracer bullets and have six grooves, right-hand twist, one turn in 7 in (1:177.8 mm or 32 calibers). M193 ball and M196 tracer bullets may be fired in
9100-423: The M16A4 is the fourth generation of the M16 series. It is equipped with a removable carrying handle and quad Picatinny rail for mounting optics and other ancillary devices. The M16 has also been widely adopted by other armed forces around the world. Total worldwide production of M16s is approximately 8 million, making it the most-produced firearm of its 5.56 mm caliber. The US military has largely replaced
9230-486: The M4 carbine. The troops did not report reliability problems with their rifles. While only 100 troops were asked, they engaged in daily fighting in Marja , including at least a dozen intense engagements in Helmand Province , where the ground is covered in fine powdered sand (called "moon dust" by troops) that can stick to firearms. Weapons were often dusty, wet, and covered in mud. Intense firefights lasted hours with several magazines being expended. Only one soldier reported
9360-694: 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 StG 45 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
9490-561: The Red Army's new mobile warfare doctrines. In the 1960s, the Soviets introduced the RPK light machine gun , itself an AK-47 type weapon with a bipod , a stronger receiver, and a longer, heavier barrel that would eventually replace the RPD light machine gun. 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
9620-541: 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 World War II, German technicians involved in developing the Sturmgewehr 45 , continued their research in France at CEAM. The StG 45 mechanism was modified by Ludwig Vorgrimler and Theodor Löffler at
9750-615: The Sturmgewehr 44 was "intended in a general way to serve the same purpose as the U.S. carbine" and was in many ways inferior to the M1 carbine, and was of "little importance". 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 . Early experiments with select-fire versions of
9880-486: The TKB-0111, AEK-971 and AKB. The AS/ASM and TKB-0146 showed excellent accuracy. Testers and members of the commission all noted the great comfort with which both of these weapons could be fired. The recoil was also light enough that the weapons could be fired without having to shoulder them. Both were capable of firing a two-shot burst at such a high rate of fire that it sounded like a single shot. Observers could also see
10010-659: The U.S. Army's definition. For example: In the United States, selective-fire rifles are legally defined as " machine guns ", and civilian ownership of those has been tightly regulated since 1934 under the National Firearms Act and since 1986 under the Firearm Owners Protection Act . However, the term "assault rifle" is often conflated with " assault weapon ", a U.S. legal category with varying definitions which includes many semi-automatic weapons. This use has been described as incorrect and
10140-467: The U.S. Army's order of 85,000 XM16E1s; and to appease General LeMay, the Air Force was granted an order for another 19,000 M16s. In March 1964, the M16 rifle went into production and the Army accepted delivery of the first batch of 2,129 rifles later that year, and an additional 57,240 rifles the following year. In 1964, the Army was informed that DuPont could not mass-produce the IMR 4475 stick powder to
10270-433: The Vietnam War. M16s were produced by Colt until the late 1980s when FN Herstal (FN USA) began to manufacture them. During the early part of its service, the M16 had a reputation for poor reliability and a malfunction rate of two per 1000 rounds fired. The M16's action works by passing high-pressure propellant gasses, tapped from the barrel, down a tube and into the carrier group within the upper receiver. The gas goes from
10400-419: The adoption of assault rifles by the rest of NATO. By the end of the 20th century, assault rifles had become the standard weapon in most of the world's armies, replacing full-powered rifles and submachine guns in most roles. The two most successful modern assault rifles are the AK-47 and the M16 designs and their derivatives. The term assault rifle is generally attributed to Adolf Hitler , who used
10530-587: The assault rifle concept. Today, the term assault rifle is used to define firearms sharing the same basic characteristics as the StG 44. The U.S. Army defines assault rifles as "short, compact, selective-fire weapons that fire a cartridge intermediate in power between submachine gun and rifle cartridges." In this strict definition, a firearm must have at least the following characteristics to be considered an assault rifle: Rifles that meet most of these criteria, but not all, are not assault rifles according to
10660-468: The bolt carrier during operation increases the amount of heat that is deposited in the receiver while firing the M16 and causes the essential lubricant to be "burned off". This requires frequent and generous applications of appropriate lubricant. Lack of proper lubrication is the most common source of weapon stoppages or jams. The original M16 fared poorly in the jungles of Vietnam and was infamous for reliability problems in harsh environments. Max Hastings
10790-413: The bore also reduces muzzle rise, especially during automatic fire. Because recoil does not significantly shift the point of aim, faster follow-up shots are possible and user fatigue is reduced. In addition, current model M16 flash-suppressors also act as compensators to reduce recoil further. Notes: Free recoil is calculated by using the rifle weight, bullet weight, muzzle velocity, and charge weight. It
10920-463: The cartridge case was not contracted enough during extraction due to the longer peak pressure period. The ejector would then fail to extract the cartridge case, tearing through the case rim, and leaving an obturated case behind. After the introduction of the M4 carbine, it was found that the shorter barrel length of 14.5 inches also harms the reliability, as the gas port is located closer to the chamber than
11050-502: The charging handle was re-located from under the carrying handle like it was on AR-10 to the rear of the receiver), the newly redesigned rifle was subsequently adopted as the M16 Rifle. "(The M16) was much lighter compared to the M14 it replaced, ultimately allowing soldiers to carry more ammunition. The air-cooled, gas-operated, magazine-fed assault rifle was made of steel, aluminum alloy and composite plastics, truly cutting-edge for
11180-512: The charging handle was re-located from under the carrying handle like the AR-10, to the rear of the receiver), the newly redesigned rifle was renamed the Rifle, Caliber 5.56 mm, M16 . Inexplicably, the modification to the new M16 did not include a chrome-plated barrel. Meanwhile, the Army relented and recommended the adoption of the M16 for jungle warfare operations. However, the Army insisted on
11310-574: 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 , which replaced the M1919 Browning machine gun in major combat roles. Its NATO partners adopted the FN FAL and Heckler & Koch G3 rifles, as well as the FN MAG and Rheinmetall MG3 GPMGs. The FN FAL
11440-480: 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 metres or 2,000 feet). Also during
11570-475: 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
11700-523: The gas port of the standard length M16 rifle: 7.5 inches instead of 13 inches. This affects the M4's timing and increases the amount of stress and heat on the critical components, thereby reducing reliability. In a 2002 assessment, the USMC found that the M4 malfunctioned three times more often than the M16A4 (the M4 failed 186 times for 69,000 rounds fired, while the M16A4 failed 61 times). Thereafter,
11830-415: The gas tube, through the bolt carrier key, and into the inside of the carrier where it expands in a donut-shaped gas-piston cylinder. Because the bolt is prevented from moving forward by the barrel, the carrier is driven to the rear by the expanding gases and thus converts the energy of the gas to the movement of the rifle's parts. The back part of the bolt forms a piston head and the cavity in the bolt carrier
11960-463: The general guidance of TsNIITochMash (Central Research Institute for Precision Machine Building). By August 1984, eight prototypes from eight designers were ready to be tested. Preliminary trials on the technical design stage in August and November 1984 were subjected to assault rifles: The Commission, appointed by the decision Ministry of Defence and GRAU , reviewed the test results and confirmed
12090-442: The inclusion of a forward assist to help push the bolt into battery if a cartridge failed to seat into the chamber. The Air Force, Colt, and Eugene Stoner believed that the addition of a forward assist was an unjustified expense. As a result, the design was split into two variants: the Air Force's M16 without the forward assist, and the XM16E1 with the forward assist for the other service branches. In November 1963, McNamara approved
12220-578: The magazine release, and revised flash hider. In 1983, the US Marine Corps adopted the M16A2 rifle, and the US Army adopted it in 1986. The M16A2 fires the improved 5.56×45mm (M855/SS109) cartridge and has a newer adjustable rear sight, case deflector, heavy barrel, improved handguard , pistol grip, and buttstock , as well as a semi-auto and three-round burst fire selector. Adopted in July 1997,
12350-406: The now-familiar hinge and takedown pins, and the charging handle was on top of the receiver placed inside of the carry handle. For a 7.62 mm NATO rifle, the AR-10 was incredibly lightweight at only 6.85 lb (3.11 kg) empty. Initial comments by Springfield Armory test staff were favorable, and some testers commented that the AR-10 was the best lightweight automatic rifle ever tested by
12480-482: The past 12 months. Only troops who had fired their weapons at enemy targets were allowed to participate. 1,188 troops were armed with M16A2 or A4 rifles, making up 46 percent of the survey. 75 percent of M16 users (891 troops) reported they were satisfied with the weapon. 60 percent (713 troops) were satisfied with handling qualities such as handguards, size, and weight. Of the 40 percent dissatisfied, most were with its size. Only 19 percent of M16 users (226 troops) reported
12610-488: The photographs remained classified into the 1980s. 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. U.S. Secretary of Defense Robert McNamara now had two conflicting views: the ARPA report favoring the AR-15 and the Army's position favoring the M14. Even President Kennedy expressed concern, so McNamara ordered Secretary of
12740-423: The possibility of finding a candidate that meets the initial ROC specifications. Two designs were eliminated after this first stage of testing: the automatic APT, because of its unreliability, and the TKB-0111 (the least promising). The remaining designs went through 18 months of further development to improve manufacturing details and accuracy. From May to June 1986, following the 18-month development period, one of
12870-402: The previous tests, selecting tests that would favor the M14 and choosing match grade M14s to compete against AR-15s out of the box. At this point, the bureaucratic battle lines were well-defined, with the Army ordnance agencies opposed to the AR-15 and the Air Force and civilian leadership of the Defense Department in favor. In January 1963, Secretary of Defense Robert McNamara concluded that
13000-405: The rear. Instead of connecting or other mechanical parts driving the system, high-pressure gas performs this function, reducing the weight of moving parts and the rifle as a whole. The M16 uses a "straight-line" recoil design, where the recoil spring is located in the stock directly behind the action, and serves the dual function of operating spring and recoil buffer. The stock being in line with
13130-495: The receiver housing, stock, trigger group (including the fire control selector and firing mechanism parts), magazine well, handguard and carrying handle are all made of a carbon fiber -reinforced polyamide . The receiver has an integrated steel barrel trunnion (with locking recesses) and a nylon 66 steel reinforced receiver. The standard Bundeswehr versions of the G36 are equipped with a unique ZF 3×4° dual optical sight that combines
13260-659: The remaining six designs, the AL-9 was replaced by the AKB-1 and new prototype was added, the AO-63 assault rifle (designed by S.G. Simonov and P.A. Tkachev ). Tests included firing a high volumes of rounds under extreme conditions including dust, extreme temperatures and altitudes. No prototype met all requirements. Only the AS and AO-63 met the requirement of accurate grouping. Designers were given three months to update their designs before
13390-406: The rifle was initially delivered without adequate cleaning kits or instructions because advertising from Colt asserted that the M16's materials made the weapon require little maintenance, leading to a misconception that it was capable of self-cleaning. Furthermore, cleaning was often conducted with improper equipment, such as insect repellent , water, and aircraft fuel, which induced further wear on
13520-423: The same weight compared to the larger and heavier 7.62×51mm NATO cartridge. The 5.56mm cartridge is also much easier to shoot. In 1961 marksmanship testing, the U.S. Army found that 43% of AR-15 shooters achieved Expert, while only 22% of M-14 rifle shooters did so. Also, a lower recoil impulse, allows for more controllable automatic weapons fire. In March 1970, the U.S. recommended that all NATO forces adopt
13650-400: The slow 1 turn in 14-inch (360 mm) rifling twist rate. However, any pointed lead core bullet will "tumble" after penetration into flesh, because the center of gravity is towards the rear of the bullet. The large wounds observed by soldiers in Vietnam were caused by bullet fragmentation created by a combination of the bullet's velocity and construction. These wounds were so devastating that
13780-497: The soldier to push on; that maybe this would be a comforting feeling to him or something." After modifications, the new redesigned rifle was subsequently adopted as the M16 Rifle: (The M16) was much lighter compared to the M14 it replaced, ultimately allowing soldiers to carry more ammunition. The air-cooled, gas-operated, magazine-fed assault rifle was made of steel, aluminum alloy, and composite plastics, truly cutting-edge for
13910-549: The specifications demanded by the M16. Therefore, Olin Mathieson Company provided a high-performance ball propellant . While the Olin WC 846 powder achieved the desired 3,300 ft (1,000 m) per second muzzle velocity, it produced much more fouling, which quickly jammed the M16's action (unless the rifle was cleaned well and often). In March 1965, the Army began to issue the XM16E1 to infantry units. However,
14040-441: The stock was plastic to reduce weight. In 1958, the Army's Combat Developments Experimentation Command ran experiments with small squads in combat situations using the M14, AR-15, and Winchester's Light Weight Military Rifle (WLWMR). The resulting study recommended adopting a lightweight rifle like the AR-15. In response, the Army declared that all rifles and machine guns should use the same ammunition and ordered full production of
14170-463: The summer of 1961, General LeMay was promoted to U.S. Air Force chief of staff and requested 80,000 AR-15s. However, General Maxwell D. Taylor , chairman of the Joint Chiefs of Staff , advised President John F. Kennedy that having two different calibers within the military system at the same time would be problematic and the request was rejected. In October 1961, William Godel, a senior man at
14300-483: The tests were repeated in late October 1986. Two designs were modified fundamentally for this round of testing; the ASM construction by Nikonov (shift in momentum returns in the stationary store) and the battery instead of AKB-1 design Kalashnikov (balanced automatics). Further developments of the prototypes were limited to muzzle devices. Halfway through the tests it became clear that it was not viable to continue further work
14430-459: The time. Designed with full and semi-automatic capabilities, the weapon initially did not respond well to wet and dirty conditions, sometimes even jamming in combat. After a few minor modifications, the weapon gained in popularity among troops on the battlefield. Despite its early failures the M16 proved to be a revolutionary design and stands as the longest continuously serving rifle in US military history. It has been adopted by many US allies and
14560-527: The time. Designed with full and semi-automatic capabilities, the weapon initially did not respond well to wet and dirty conditions, sometimes even jamming in combat. After a few minor modifications, the weapon gained in popularity among troops on the battlefield." Despite its early failures, the M16 proved to be a revolutionary design and stands as the longest continuously serving rifle in American military history. It has been adopted by many U.S. allies and
14690-565: The trajectory of the two bullets. Eventually, the AS/ASM was selected and designated the AN-94 (Assault-rifle, Nikonov, 1994). M16 rifle The M16 rifle (officially designated Rifle, Caliber 5.56 mm, M16 ) is a family of assault rifles adapted from the ArmaLite AR-15 rifle for the United States military . The original M16 rifle was a 5.56×45mm automatic rifle with
14820-478: The weapon to various propellant and projectile or barrel length specific pressure behavior. The M16A1 was especially lightweight at 7.9 pounds (3.6 kg) with a loaded 30-round magazine. This was significantly less than the M14 that it replaced at 10.7 pounds (4.9 kg) with a loaded 20-round magazine. It is also lighter when compared to the AKM 's 8.3 pounds (3.8 kg) with a loaded 30-round magazine. The M16A2 weighs 8.8 lb (4.0 kg) loaded with
14950-506: The weapon. As a result, reports of stoppages in combat began to surface. The most severe problem was known as "failure to extract"—the spent cartridge case remained lodged in the chamber after the rifle was fired. Documented accounts of dead U.S. troops found next to disassembled rifles eventually led to a Congressional investigation: We left with 72 men in our platoon and came back with 19. ...Believe it or not, you know what killed most of us? Our own rifle. Practically every one of our dead
15080-472: The worldwide trend toward small caliber, high-velocity cartridges. Following the adoption of the M16, carbine variants were also adopted for close quarters operations. The AR-15 family of weapons served through the Vietnam War. However, these compact assault rifles had design issues, as "the barrel length was halved" to 10 inches (250 mm) which "upset the ballistics", reducing its range and accuracy and leading "to considerable muzzle flash and blast, so that
15210-469: Was a Soviet answer to the U.S. M16. The Soviet military realized that the M16 had better range and accuracy over the AKM, and that its lighter cartridge allowed soldiers to carry more ammunition. Therefore, in 1967, the USSR issued an official requirement to replace the AKM and the 7.62×39mm cartridge. They soon began to develop the AK-74 and the 5.45×39mm cartridge. AK-74 production began in 1974, and it
15340-407: Was developed by shortening the standard 7.92×57mm Mauser round and giving it a lighter 125-grain bullet, which limited range but allowed for more controllable automatic fire. A smaller, lighter cartridge also allowed soldiers to carry more ammunition "to support the higher consumption rate of automatic fire". The Sturmgewehr 44 features an inexpensive, easy-to-make, stamped steel design and
15470-1027: Was factory adjusted to be parallax-free at 200 yd (183 m). In Delft, the Netherlands Artillerie-Inrichtingen produced a roughly similar 3×25 telescopic sight for the carrying handle mounting interfaces. The M16 elevated iron sight line has a 19.75 in (502 mm) sight radius. As the M16 series rear sight, front sight and sighting in targets designs were modified over time and non-iron sight (optical) aiming devices and new service ammunition were introduced zeroing procedures changed. The standard pre-M16A2 "Daylight Sight System" uses an AR-15-style L-type flip, two aperture rear sight featuring two combat settings: short-range 0 to 300 m (0 to 328 yd) and long-range 300 to 400 m (328 to 437 yd), marked 'L'. The pre-M16A2 "Daylight Sight System" short-range and long-range zeros are 250 and 375 m (273 and 410 yd) with M193 ammunition. The rear sight features
15600-638: Was first used in the semi-automatic SKS carbine and the RPD light machine gun . Hugo Schmeisser , the designer of the Sturmgewehr, was captured after World War II, and, likely, helped develop the AK-47 assault rifle, which would quickly replace the SKS and Mosin in Soviet service. The AK-47 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 were perfectly suited for
15730-424: Was found with his (M16) torn down next to him where he had been trying to fix it. In February 1967, the improved XM16E1 was standardized as the M16A1. The new rifle had a chrome-plated chamber and bore to eliminate corrosion and stuck cartridges, and other minor modifications. New cleaning kits, powder solvents, and lubricants were also issued. Intensive training programs in weapons cleaning were instituted including
15860-437: Was ignored and the Army referred to the .30 in (7.62 mm) caliber as "full-sized" for the next 35 years. 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
15990-400: Was insufficient to meet the needs of the armed forces and ordered a halt to M14 production. At the time, the AR-15 was the only rifle that could fulfill a requirement of a "universal" infantry weapon for issue to all services. McNamara ordered its adoption, despite receiving reports of several deficiencies, most notably the lack of a chrome-plated chamber. After modifications (most notably,
16120-403: 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 2.7 kg (6 lb) when loaded with
16250-519: 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 Heckler & Koch G3 is a 7.62×51mm, selective fire, automatic rifle produced by the German armament manufacturer Heckler & Koch GmbH (H&K) in collaboration with
16380-441: Was responsible for the name Sturmgewehr , and Hitler had no input besides signing the production order . Furthermore, Hitler was initially opposed to the idea of a new infantry rifle, as Germany lacked the industrial capacity to replace the 12,000,000 Karabiner 98k rifles already in service, only changing his mind once he saw it first-hand. The StG 44 is generally considered the first selective fire military rifle to popularize
16510-498: Was the low accuracy of short bursts of fire. Soviet analysts determined that modern battlefield tactics require short bursts of fire from shooting positions including standing, kneeling and prone (lying down). The requirement for more accurate bursts of fire was one of the most important aspects of the Required Operational Capability (ROC) specification for any replacement of the AK-74. Therefore, in 1981
16640-603: Was unveiled in 1977, when it was carried by Soviet parachute troops during the annual Red Square parade . It would soon replace the AKM and become the standard Soviet infantry rifle. In 1979, the AK-74 saw combat for the first time in Afghanistan , where the lethality of the 5.45mm rounds led to the Mujahadeen dubbing them "poison bullets". The adoption of the 5.56mm NATO and the Russian 5.45×39mm cartridges cemented
16770-582: Was used more substantially in the Russian Civil War and in the Winter War . Some consider it to be an "early predecessor" or "ancestor" of the modern assault rifle. 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 metres (1,300 ft) and that contemporary rifles were overpowered for most small arms combat. They would soon develop
16900-465: Was very critical of the M16's general field issue in Vietnam just as grievous design flaws were becoming apparent. He further states that the Shooting Times experienced repeated malfunctions with a test M16 and assumed these would be corrected before military use, but they were not. Many marines and soldiers were so angry with the reliability problems they began writing home and on 26 March 1967,
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