Development course of M 16 series automatic rifles
At the same time, Winchester also joined the competition. Based on the design of M 1 carbine, they provided a .224 caliber light military rifle (LMR). In order to defeat their opponents, stoner asked Remington to improve their .222 bullets. This produced Remington rifle bullets. 223。 Ar 15 started the experiment in the army on March 3 1 day, 1958, and the army compared ar15 and M 14.
By this time, Fairchild has spent $6.5438+0.45 million on AR 15, but the future is still unclear. 1959, the AR 15 patent was sold to Colt for $75,000 in cash. 1960, stoner left Amaret (Amaret belongs to Fairchild Engine and Aircraft Manufacturing Company).
Colt decided to bet his future on AR 15. 1962, the us air force purchased 8500 AR- 15 rifles for the first time to equip the airport security forces. 1964 the army officially equipped the gun. 1On February 8, 964, the US Air Force officially named XM 16 as "American 5.56mm M 16 rifle.
The M 16 rifle exposed many problems on the battlefield in Vietnam, such as serious dirty bore, jam, broken shell, damaged magazine and lack of wiping tools. The reason is that Vietnam has a humid climate and high temperature, and guns are prone to rust. The production process of M 16 lacks supervision. But the main ammunition problem. The original M 193 used the original DuPont IMR4475 single-base tubular explosive, but in 1964, the Army decided to use WC846 of Olin Company as the charge, and the original T65 bomb also used this charge. However, the charge is dirty, but the barrel and bore of M 16 are not chrome plated, and the military is told that it is an epoch-making weapon and does not need much cleaning (lack of wiping tools). So Colt Company began to improve and named it M 16A 1, 1967, which was adopted by the military on February 28th.
NATO small caliber rifles from 1977 to 1980 were selected and tested, and it was determined that Belgian SS 109 type 5.56 mm bullets were NATO standard caliber bullets, while M 16A 1 type rifles could only use American M 193 type 5. In order to unify NATO caliber, in 1982, the US Marine Corps purchased 200,000 improved M 16A 1 rifles for the first time and named them M 16A2 rifles. 1984 In March, the US Army officially announced the adoption of the M 16A2 rifle.
The M 16 series rifles are equipped in 55 countries and regions, including Australia, Chile, Dominica, Haiti, Italy, Jordan, Japan, Indonesia, South Korea, New Zealand, Lebanon, Sri Lanka, Viet Nam and Taiwan Province Province of China. SALVO project
1948, the military funded the establishment of a private research institute-the combat research laboratory, imitating similar combat research institutes in Britain. One of their first jobs was to study bulletproof vests, and soon they came to the conclusion that they needed to know more about battlefield casualties in order to make reasonable suggestions. After that, it analyzes the reports of more than 3 million battlefield casualties in two world wars. In the next few years, they published a series of reports based on their findings.
Their basic conclusion is that most of the fighting takes place at close range. In a highly mobile war, the combat form of troops is mainly encounter. At this time, the side with stronger firepower wins. They also found that the probability of being hit in battle is random, that is to say, accurate aiming is meaningless because the target is no longer static. The most accurate casualty rate indicator is the total number of bullets fired. Their conclusion suggests that infantry should be equipped with fully automatic rifles to increase the chances of firing. However, this kind of weapon will also greatly increase the consumption of ammunition. In order for an infantry to have enough ammunition to support a battle, they need to use some much lighter weapons and equipment. It is worth noting that this study was conducted in secret when the United States and Britain were arguing over which caliber bullets were better or worse .28 and.30.
For all these reasons, existing rifles are difficult to adapt to real-world battles. Although it seems that the new T44 (the predecessor of M14 automatic rifle) can improve the firing rate, its heavy ammunition box makes the carrying capacity of individual ammunition a big problem. In addition, the length and weight of this gun make it unsuitable for short-distance combat. Therefore, a smaller and lighter weapon is needed to be put into use faster.
These efforts have not escaped the attention of Rena Stadhle, director of small arms research and development of the US Army Ordnance Department. He is dissatisfied with the involvement of non-governmental research institutions in his research scope. At this time, the Army Ordnance Department began to support the powerful bullet developed by Springfield Arsenal for T25, which was before T44 appeared. Finally, he asked Aberdeen Range to submit a report on small caliber weapons. However, when Donald Hull, the principal researcher appointed by Rena, found that in most battles, a bullet with a size of .22 inches (5.59 mm) had the same performance as a bullet larger than it, the plan went wrong. When a weapon may have a higher firing rate because of its low recoil, it will cause more casualties. Donald Hull's colleagues, especially Williams Davis Jr and G.A. Gastafson, began to study a series of experimental .224-inch (5.69mm) bullets. 1955, their request to increase the research budget was rejected.
At the same time, a new research project of the US Army, SALVO (salvo), was set up to find a weapon that meets the needs of actual combat. In the two-stage plan before 1953 to 1957, SALVO gradually found that if a weapon can fire four bullets in a row and disperse them in a square of 20 inches (0.5 meters), its hit rate will be twice that of the existing semi-automatic weapons. In the second phase plan SALVO II, several experimental conceptual weapons were tested. Alvin Barr of AAI Company proposed a series of dart weapons. The first is a 32-dart shotgun, and the last is a single-dart rifle. Springfield Arsenal and Winchester Lianfa Weapons Company produce multi-barrel weapons. The design of the Combat Research Laboratory itself uses two new types of bullets. The 0.22, 0.25 or 0.27 warhead is installed in the 0.308 in Winchester or 0.30-06 in Springfield.
Eugene stoner
While the T44 test continued, the Belgian Gestel National Arsenal also submitted their new weapon FN FAL automatic rifle, code T48, through Harrington-Richardson Weapons Company of the United States. However, the test results have obviously been abandoned. T44 was chosen as the new military rifle of the US Army, not its strong competitor T48. Before T44 was selected, a new rifle entered the competition. 1954, Eugene Stoner of newly established Amarette company led the development of AR- 10. T44 in Springfield and other similar models are traditional wooden rifles for furniture, or all made of steel, mainly using cast and machined parts. Amarette was established to apply the latest technology and alloy materials to gun design, and Stoner felt that it should be easy to beat other competitors.
Stoner's design was brand new from the beginning. The barrel is combined, except for the stainless steel barrel with rifle wire, there is also a hard aluminum alloy liner with good heat dissipation. The shell is made of cast aluminum and ground aluminum instead of U steel. The barrel and housing are connected by an independent hardened steel adapter, which locks the bolt. This makes it possible to lock between steels when using a lightweight aluminum shell. The high-pressure propellant gas driving the bolt is led out from the front end of the barrel and directly enters the piston cavity formed between the bolt bracket and the bolt, and the bolt itself is equivalent to the piston. Traditional rifles put this piston chamber and piston near the air guide hole. Its stock and grip are made of glass fiber shell and hard plastic core. Muzzle arresters are even made of titanium.
At the same time, the layout of this gun is not the same. The typical design is to put the sight near the top of the barrel, and transfer the recoil to the shoulder with the downward bending of the stock, so that the sight is just at the same height as the eyes. However, this means that the shoulder position is lower than the axis of the gun bore, so the gun is easy to cause the muzzle to jump up when shooting, which is very difficult to control, especially when shooting automatically. Amarette used the design of German MG42 general machine gun and M 194 1 Johnson light machine gun for reference, put the barrel and butt on a line, just below the eyes, then raised the sight and installed the door ruler on the handle. The handle also includes a handle at the top of the box.
AR- 10 was a very advanced design at that time. It uses the same bullet as T44. Although it is two pounds (900 grams) lighter than similar guns, it also significantly improves recoil control. However, it was launched too late, even in a hurry. Since then, its unusual design has not found any followers among traditional large arms dealers. In 1957, AR- 10 was disqualified because an aluminum barrel with a stainless steel liner burst during the test. But it still provides a concept for the development of new small caliber high-speed guns in the future. 1957, a grant application written by gustafson in 1955 reached the hands of General Will Weiman of the American Continental Army Command. He immediately set up a team to develop a .22 caliber (5.6 mm) weapon for testing. Their ultimate requirement is that a weapon with optional firing mode weighs about 6 pounds (2.7 kilograms) when it is filled with 20 bullets. Its bullet should be able to penetrate a standard American helmet bulletproof vest 500 yards (460 meters) away or a 0. 135 inch (3.4 mm) steel plate. At the same time, its damage ability should reach or exceed .30 carbine.
After seeing the previous AR- 10, Weiman personally suggested Amarit to develop a new weapon for testing. At that time, stoner was working hard for the new version of AR- 10 AR- 16, but stoner accepted the challenge as the design team led by the chief designer. Their first design used traditional layout and wood, but it turned out to be too light. When using traditional stock, even light ammunition, the control of recoil becomes a problem. Their second design was only a scaled-down version of AR- 10, but it soon proved to be more successful. The new gun was named AR- 15. At the same time, Winchester Company introduced the design of M 1 carbine on their basis. Eli Harvey of Springfield Arsenal also tried to launch a new design, but his boss in Springfield refused because they refused to transfer T44 resources.
In the end, Amarette's AR- 15 has no real competitors. The new .223 Remington rifle bullet was developed by Remington Company to meet the penetration requirements. Light ammunition makes it smaller than AR- 10. Even if the barrel is changed to a simple all-steel type, it is still lighter than Winchester's design by more than one pound (450g). The latter's empty gun weighs 2.89 kilograms, while it weighs 3.5 kilograms when it is full of ammunition.
Its only problem is that nine months later, on March 3 1, 1958, when the military started testing, the development process of AR- 15 was not completely completed. When rainwater enters the barrels of Amarette AR- 15 and Winchester's sample guns, it will cause the gun bore to explode, which makes the army wait for a bigger bullet again, this time it is .258 inches (6.55 mm). Nevertheless, they suggested that the experiment in cold weather should be carried out in Alaska. Stoner later flew to Alaska to replace some parts, but when he arrived, he found that the rifle was wrongly reassembled. stoner believed that this was due to improper operation and asked for re-testing. When he returned, he was surprised to find that before he arrived, the military had overturned his design, and their report also surprisingly suggested the use of .258 inch (6.55 mm) bullets. After reading these reports, General maxwell taylor resolutely opposed this design and forced the production of M 14 automatic rifles to continue.
Not all the reports are negative. In a series of simulated combat tests of AR- 15, M 14 and AK-47, the military found that the small size and light weight of AR- 15 enabled it to quickly put into combat, just as the Continental Army Command said. Their final conclusion is that an eight-man squad equipped with AR- 15 can have the same firepower as an eleven-man squad equipped with M 14. They also found that AR- 15 is more reliable than M 14 after firing 1000 rounds, and the probability of firing interruption and jamming is less.
At this time, Fairchild Company, which founded Amarette, has spent 654.38+0.45 million yuan as research expenses, which seems to be far from over. 1959 65438+In February, Fairchild sold the production rights of AR- 15 to Colt Light Weapons Company, and only spent 15000 USD in cash and 4.5% of the sales after guarantee payment. 1960, Amarette reorganized and Stoner left. Colt further improved the design of AR- 15, and began to lobby the military high-level. 1June, 960, Curtis Flamel, Deputy Chief of Staff of the Air Force, visited the AR- 15 demonstration. He immediately ordered 8500 units to be used for the defense of strategic air bases. Colt also negotiated with the Advanced Research Projects Agency (ARPA) of the Ministry of National Defense, which purchased 1000 rifles for the South Vietnamese troops in the early summer of 1962, and conducted a comprehensive actual combat test. The special forces of the United States, which cooperated with the South Vietnamese forces, submitted an important battlefield report, emphasizing the necessity of adopting AR-65,438+05 immediately. However, the US Army re-examined AR- 15 twice in 1962 and 1963, and both times rejected AR- 15. However, after hard work, the Ministry of National Defense decided to test the effectiveness-cost ratio of AR- 15 and M 14. The results show that the firepower of AR- 15 is equivalent to that of AK-47, and the price is lower.
Robert mcnamara, the US Secretary of Defense, has two contradictory views: the ARPA report is biased towards AR- 15, and the Pentagon affirms M 14. Even President John F. Kennedy expressed concern about this incident. So McNamara ordered Army Secretary cyrus vance to test M 14, AR- 15 and AK-47. The army's test report shows that M 14 is suitable for use in the army, but Vance suspects that these test methods are unfair. He ordered the army inspector general to investigate the methods used in these tests, and the latter's comprehensive report pointed out that the army testers were obviously biased towards M 14. Colt began to take advantage of this incident, and they used the folk media to accuse the military testers of being too partial to M 14.
The test record proves that AR- 15 is indeed better than M 14, and Colt has gained political support. General William Westmoreland, commander of the US military stationed in Vietnam, put forward equipment requirements, and McNamara ordered M 14 to stop production in June 1963. 165438+1October, the army ordered 85000 XM 16E 1 for testing, and the air force ordered 19000. At the same time, the Army is carrying out another project, namely the Light Weapons System (SAWS), which aims at weapons suitable for the general army. They strongly recommend the immediate use of this weapon, which is actually a disguised boycott of AR- 15, 1963. At the end of 1963, the air force officially received the first batch of XM 16. At that time, the unofficial name of the gun was M 16. 1In February 1964, the Air Force officially named AR- 15 as an American 5.56 mm M 16 rifle. M 16 of the air force is different from XM 16E 1 of the army. As will be mentioned later, the latter has a reentry booster. The Air Force's M 16 only made minor changes to AR- 15.
1965 When M 14 arrived in Vietnam with the US military, some defects in its use began to become obvious. After nearly 20 years of experiments, it took the army a long time to get the design of M 14. Although M 14 may be a good substitute for M 1 Garland rifle, it is not a good M65438+. The M 14 will be too large to play an effective role in narrow areas or jungle areas, although it is lighter than many guns designed for fighting in narrow areas. Its ammunition is lighter than .30-06, which means that it can carry more bullets when patrolling, but it is still heavier than .30 carbine bullets, so the ammunition carrying capacity is still limited. Automatic shooting is often criticized as a waste of ammunition, and bullets are powerful. Recoil makes it difficult for the shooter to shoot accurately in automatic shooting. Therefore, the progressive rifle is locked in the semi-automatic shooting mode. Finally, the army spent a lot of time and money to replace a semi-automatic gun with another weapon with long service life but small size. It will soon be replaced, even if it seems to be the result of internal political struggle. In the defense war designed by M 14, M 14 developed from Garland rifle is more reliable. When M 16 is carrying out TCC and many improvements to enhance its reliability, M 14 is getting less and less attention and is not suitable for fighting in the jungle environment.
At the same time, facing the Soviet-made AK-47, the troops are also frantically trying to increase their firepower. They improvise and use whatever weapons they can find, such as thompson submachine gun's weapons from the pre-World War II period. The American army on the battlefield in Vietnam urgently needs a new type of portable rifle. XM 16E 1 was mass-produced without adequate testing, but it soon got a bad review. Since the autumn of 1966, there have been frequent failures on the battlefield in Vietnam.
For XM 16E 1, the Pentagon ordered the propellant of its bullets to be changed from single-base tubular charge to finer double-base spherical charge. This increases the automatic firing rate, and makes the parts of the gun rust faster, and also increases the dirt, which often leads to the phenomenon of jamming and shell breakage. Some problems caused by this simple change were condemned. The failure of ignition interruption is usually due to rusty combustion chamber or propellant residue, poor maintenance, worn parts or all these factors. For more dirt, the solution is to redesign the buffer to reduce the circulation rate of fire, and the damage rate of parts will return to normal level. As a legacy, spherical charges are still used to distribute ammunition today.
The auxiliary locking device of the bolt is for some reason. When the buffer spring can't reset the bolt successfully, it can reset and lock the bolt manually. This piston-shaped bolt auxiliary locking device located on the right side of the shell is the obvious difference between XM 16E 1 and M 16. Colt Company, Air Force Marine Corps and Eugene stoner Company all think that it is unnecessary to add this complicated device, and therefore the rifle procurement cost is increased by $4.50, and there is no practical benefit. But three years later, on February 28th, 1967, the army ordered 840,000 rifles of this version, which was later called M 16A 1.
Colt exaggerated the reliability of the M 16 test, claiming that guns never need cleaning. Although this statement may be true for the original IMR charge, it is not true for the finer, faster burning and dirtier spherical charge. The pneumatic control system that directly pushes the frame uses the air passage at the top of the barrel to lead the gas out to the "piston chamber" behind the bolt and the groove of the frame. When the burning gases come to this area, they drive the frame to move backward, and then discharge the excess gas through the shell throwing window and the space between the gas key at the top of the frame and the trachea in the barrel. The traditional design is to keep the piston above or below the barrel, and then exhaust excess gas from it. The advantage of Stoner system is that the "piston" formed by bolt and bolt bracket runs in a straight line and is coaxial with the bore. Therefore, when the gun frame moves, the bore axis will not move in the opposite direction. Eliminating a separate piston also makes the operation easier because there are fewer moving parts. The disadvantage of this design is that the gunpowder gas will be sent directly to the breech, which is easy to deposit carbon in the bolt assembly. Therefore, M 16 needs to be cleaned and lubricated frequently to maintain its reliability.
To make matters worse, the troops were told that they were not equipped with cleaning tools because they were epoch-making weapons and did not need cleaning. As a result, M 16 often has some faults, such as jam, serious dirt in the gun bore, corrosion of gun tube and gun bore, shell breakage, magazine damage and so on. Soldiers often laugh at these "toy guns" and describe those broken guns in one sentence: "You can call them Mattel". This sentence later evolved into a folklore, and the content was that the first batch of M 16 was partially or completely made by toy manufacturers.
Within the army and the government, there was another argument about M 16. Stoner's latest design, a weapon series named stoner 63, was sent to Viet Nam for testing. SPIW, the darts weapon test program has started again. Fortunately, a cool head dominates. A committee composed of Congress reported in 1967: "It seems that the so-called problematic M 16 is actually an excellent rifle, and all the problems found in its application are caused by poor internal management of the army." M 16 cleaning tools were produced soon. A cartoon maintenance manual was also circulated in the army to show the correct maintenance method of M 16. The reliability problem soon disappeared, although the negative evaluation of guns was not the case. But this is not the case for the North Vietnamese army that started using M 16 as soon as it was discovered.
Perhaps the most important change of M 16A 1 is the introduction of chrome plating for gun bore and chrome plating for gun barrel soon. This improvement was put forward in the initial SALVO project test, but it was later rejected because the actual efficiency-cost ratio was not high. At that time, there was no reliable way to chrome-plate a barrel with a diameter of .224 inches. The real value of chromium plating is to prevent the barrel from rusting. As an inner chamber close to a straight wall, the smallest amount of rust powder, rusty brass, sand, dirt, rust spots and even paint powder used for marking will lead to an exponential increase in friction. On the battlefield, the soldiers found that the first bullet fired would block the gun bore. This is due to the combination of rough bore, the lack of inherent front shell function of Johnson/Stonebolt and the relatively small taper of 5.56 bullet. Chromium plating can not only prevent rust, but also reduce friction. The soil that did not enter the gun bore was pressed against the shell after firing and discharged with the shell.
After a bumpy start, M 16 has proved that its reliability can meet the use requirements. At the end of 1967, the troops were asked to only change their M 16 into XM 177, which is the carbine version of the same weapon.
Light ammunition is also something that causes a lot of controversy in the field of rifles. The concept of "high-power bullet" did not die out even after many years, and the demand for increasing caliber continued until the 1980' s. Most of the arguments focused on the 7.62× 39mm bullet of the medium-power bullet used by the Soviet Union, which was smaller than the "full-power" 7.62× 54mm design they used in wartime. People in the "small caliber" camp believe that in the1970s, when the Soviet Union adopted similar (or smaller) bullets with a size of 5.45×39 mm, the new Soviet bullets had a more advanced design, which shortened the winding distance of the barrel rifling and made the warhead rotate at a high speed. Other reasons for adopting it include lighter weight, smaller recoil and higher automatic shooting dispersion accuracy. Many advantages are also used to describe M 16.