carbine

Pioneer of Small and Medium Caliber Light Weapons: American M468 Carbine

Jane's International Defense Review, published in May 2004, reported the latest masterpiece of the famous American Barrett weapons manufacturing company-M468 special carbine/bomb; In 2004, the seventh issue of Light Weapons also published an article introducing this new weapon system. M468 has attracted much attention in the field of light weapons at home and abroad. So, where is it "shocking"?

Based on demand, open up new caliber

The caliber of M468 special carbine/ammunition developed by Barrett Weapons Manufacturing Company is neither the small caliber (5.56 mm) of NATO nor the medium caliber of 7.62mm in the past, but a brand-new caliber-6.8 mm. To explore the change of this caliber, we must start with the development from 7.62 mm to 5.56 mm.

During the period of 1950, when NATO implemented the "ammunition generalization" plan, the United States resolutely opposed any small-caliber bullets with reduced power on the grounds of the long range and strong penetration of T65-type 7.62×5 1mm bullets, and exerted strong influence by virtue of its position as the alliance leader, so that NATO officially confirmed T65 bullets in 1953. The first standard rifle to use this bomb was the M 14 rifle.

T65 bullet has a large recoil when it is fired, so it is difficult for the shooter to control the weapon and the shooting accuracy is poor. The mass of bullets is too large, and the amount of bullets carried by individual soldiers does not exceed 100 rounds. In addition, the design defects of the M 14 rifle can only be fired semi-automatically, and the firepower intensity is seriously insufficient, which leads to the US military suffering in the battlefield in Vietnam. Based on this, the 5.56mm M 16 rifle was rushed into the battlefield. Later, the United States asked other NATO countries to designate 5.56mm small caliber bullets as NATO standard bullets. After selection, NATO successively designated 5.56mm M 193 and 5.56mm SS 109 as NATO standard bombs. M4, M4A 1 carbine is modified from M 16 series, and the bomb used is also SS 109 of NATO.

Although M4A 1 carbine has the advantages of portability, strong adaptability and fierce firepower, the experience from Afghanistan and Iraq shows that the short barrel of M4A 1 carbine brings low muzzle velocity and obviously reduces the effective range of 5.56mm ammunition. The temperature of barrel and front grip rises too fast; The adoption of short barrel leads to short air guide device, which makes its working pressure higher than that of M 16A2 rifle. With the increase of firing rate, the force on moving parts increases, which affects the reliability of weapons; The safety device is easy to fall off in the insurance state. Therefore, the US military began to explore alternatives to M4 series.

Generally speaking, to increase the range and power of carbine, the first effective way to consider is of course to increase the caliber of the weapon, and which caliber to adopt mainly depends on the operational needs. After investigating and comparing the bullets of 6 mm, 6.5 mm, 6.8 mm, 7 mm and 7.62 mm, the researchers of Barrett Weapons Manufacturing Company finally decided to adopt a new caliber of 6.8 mm, and developed a 6.8×43 mm special bullet accordingly.

From the change of caliber, we can see that the development of American light weapons has gone through two processes: from 7.62mm of medium caliber to 5.56mm of small caliber, and from 5.56mm of small caliber to 6.8mm close to the limit of medium and small caliber. According to the consistent practice of the United States in history, it can be predicted that the 6.8×43mm special bullet is likely to become the next generation of NATO standard bullets.

Take the road of re-playing and build a big country

As a substitute for M4 series carbine/ammunition, the requirements put forward by American special operations forces are: firstly, its power is greater than 5.56mm SS 109 bullet; Secondly, it should be changed as little as possible to ensure that it can match the existing M4 series carbine. The specific requirements are that when firing from a 406mm long barrel, the muzzle velocity of the warhead should be above 790m/s, the kinetic energy of the muzzle velocity should be above 2 330J, and the effective range of 600m should be guaranteed.

Based on these requirements, Barrett made a systematic and comprehensive study on the bullets of 6mm, 6.5mm, 6.8mm, 7mm and 7.62mm according to the usual practice. They first ruled out 7.62×5 1mm bullets, because there is no ready-made magazine that can be reliably supplied from the lower shell of M4 series carbine. Next, the comparative test of 6.8mm special bullet and 6.5mm grendel bullet was carried out. The results show that the 6.8 mm special bullet can exert greater lethality in the middle distance and has greater penetration than the NATO 5.56 mm bullet. The 6.5mm grendel bullet has good accuracy at a long distance. They finally chose the 6.8 mm special bullet because of its best combination of accuracy, lethality and reliability.

In order to increase the power of bullets, the effective technical way is to increase the quality of bullets or improve the muzzle velocity, which is also the starting point of Americans. In contrast, NATO's 5.56×45 mm warhead has a mass of 4g, while the 6.8×43 mm special bullet has a mass of 7. 5g, the difference between them is only 2mm. According to this analysis, the quality of the latter is more than 80% higher than that of the former, mainly to improve the storage speed; There is little difference in the length of ammunition, mainly considering that the new ammunition should be compatible with the existing M4 series carbine. Judging from the fact that the projectile mass of the latter is greatly increased and the muzzle velocity of the warhead is slightly lower than that of the former, it is estimated that its charge has increased.

It can be seen that the lethality and penetration rate of 6.8mm special bullets are higher than those of NATO's 5.56mm bullets and AK47' s 7.62×39mm bullets. The initial velocity of 6.8×43mm special bullet fired with 406mm barrel is 808m/s, which is higher than that of AK47100m/s..

Based on economy, reflecting multi-function

Because the M4 series carbine has been equipped with a large number of troops, it is almost impossible for the US military to completely replace it in a short time. To this end, the military requires that this new type of bullet can be applied to existing weapons without buying new weapons. This not only meets the new requirements of combat troops for weapon performance, but also fully considers the economy and saves money.

The weapon that fired this new type of bullet was designed and manufactured by Barrett Weapons Company, which is famous for manufacturing large-caliber sniper rifles. It is modified on the basis of AR 15/M 16/M4. It can fire 6.8mm bullets only by installing a new upper shell on the lower shell of the existing rifle. In addition to relevant accessories, the new upper shell only improves the barrel, barrel sleeve, shell hook and bolt machine, ensuring that the upper shell matches the existing AR 15/M 16/M4 gun system to the maximum extent. At the same time, the company also designed and developed a new gun named M468.

M468 adopts the principle of air guiding automation and the locking mechanism of bolt rotation. Ammunition supply has 5 10 or 28 magazines, double-spring shell pulling mechanism and two firing triggers. Generally, an optical sight is used, but a spare mechanical sight for inkstone hole folding is also set, which will not hinder the line of sight after being folded flat. The gun adopts the guide rail system of American ordnance company, which makes the barrel completely floating. Compared with the conventional barrel with wood protection, it enhances versatility. The diameter of M468 is obviously larger than the original 5.56mm, and the outer diameter of the barrel is increased. Therefore, it is necessary to adjust the air guide ring. Instead of grooving the traditional barrel, an ear piece is added to the air guide hoop, which is also used as a quasi-constellation. The air guide hoop is installed by rotating shaft instead of M 16 taper pin, so as to ensure that the air guide hoop is in place correctly and avoid the adverse influence of the opening of the interface slot on the thickness of the cylinder wall. According to Barrett's patented muffler design, the M468 muffler interface is a part of the air guide ring. When installing the muffler, first remove the knurled retaining ring, then screw on the muffler and lock the muffler in place with the spring lock key. When it is necessary to release, just press a button. Because the muzzle kinetic energy of this weapon is large, an efficient brake is specially designed.

Because M468 is mainly equipped with special operations troops, it also provides various accessories that can play a variety of functions. Most of the original optional accessories of M4 carbine can be used, such as "anti-fall" tactical light, front grip with spare battery, universal magazine convenient for both hands to release bamboo shoots, super holographic sight and so on. These are all aimed at making weapons fully meet the needs of special operations under various conditions.

According to the relevant data, in the shooting accuracy test, the shooting conditions are using a 406mm barrel, installing a Swarovski sight, and using a bracket with a standard number of 500 for indoor shooting. Each group has 5 rounds, and the shooting distance is 100m. As a result, the projectile dispersion is only 7.5cm. It can be predicted that with the continuous improvement of ammunition and firearms, its shooting accuracy will be further improved. Because the muzzle brake of the weapon is efficient, even if it is fired repeatedly, there is not much recoil, which is very easy to control.

Generally speaking, Barrett M468 carbine is characterized by portability, easy control, reliable action, long range and good shooting accuracy, and its terminal effect is much better than that of NATO standard 5.56mm bullet. It can be said that Barrett Gun Manufacturing Company has provided a more powerful and portable melee weapon for American special operations forces. The British tanker's new carbine is short and pithy.

The British Defence System Daily reported on June 5438+February 65438+June 2004 that the British tank crew was about to be equipped with a brand-new SA80A2 5.56mm assault rifle. H&, the British Ministry of Defence, cooperated with H&K Company and signed a contract worth100000, which converted the 1400 standard SA80 rifle into a new and shorter carbine design.

Browning 9 mm pistol. The new SA80A2 carbine will replace these two weapons from 2005. British Army Colonel Simon said: "This new carbine is a complete redesign of the SA80A2 rifle. The barrel is shortened to 304.8 mm, which is about half the length of the original barrel. Equipped with a newly developed 20-round magazine, the front grip replaces the wooden guard, making the gun lighter and easier to store and operate in the narrow space inside the tank. Additional guide rails are installed on the front gun, which can be used to install tactical lights, lasers or other capability enhancement components. The fighting capacity and reliability of this gun are equivalent to that of the SA80A2 rifle, and it is smaller, lighter and easier to use. The combination of the new design and SUSAT light weapon sight makes it a weapon with high maneuverability and high precision. "

In order to ensure that the weapon meets strict standards, researchers have tested the gun in deserts, cold regions and wet jungles. Army Colonel Deakin said: "We have conducted a series of rigorous tests on carbine in various extreme environments, and its performance exceeded our expectations. Through the test, the reliability and accuracy of the weapon are verified, which proves that the gun is easy to use in all situations, especially for tank crew who need to use it in a narrow tank space. " SC70/90 5.56mm carbine. SC70/90 is a variant of AR70/90 assault rifle developed by Beretta Company in Italy, which uses folding metal stock.

SC70/90 is mainly equipped with special forces. It only has 105 gun parts, so it is convenient and quick to assemble and disassemble. Its structure is very distinctive. For example, the gas regulator has three positions: when it is opened, it is a normal position, when it is reopened, it is used in bad weather conditions, and when it is closed, it is the position where grenades are fired.

The length of SC70/90 stock is 986 mm when it is opened, 647 mm when it is folded, and the barrel length is 450 mm. The total weight of the gun is 3.99 kg, the initial velocity of the bullet is 950 m/s, the magazine is used to load ammunition, the capacity is 30 rounds, and the NATO standard bullets are fired. Because of its durability and high reliability, it has been adopted by many countries. It is a variant of the AR70/90 assault rifle. Being able to hit grenades increases the lethality of SC70/90 carbine.

In the early 1980s, Bei Leita Company of Italy improved the 5.56mm AR70 rifle used by the special forces into an AR70/90 assault rifle according to the requirements of the Italian military, and served in the Italian army in July 1990. Later, SC70/90 carbine was developed for special forces, SCS70/90 short carbine for armored forces and S70 for infantry squad. The only difference between AR70/90 assault rifle and SC70/90 carbine is that the former uses a fixed stock, while the latter uses a folding metal stock. 80% of the parts of the two guns are interchangeable, and they are easily disassembled and combined. They are also durable and reliable. The original intention of M 1 carbine was to provide a self-defense weapon for the second-line troops to replace the standard pistol. This request was first put forward in 1938. The idea is to develop a shoulder-fired weapon similar to a carbine, which can fire medium-powered ammunition, and its range is longer than the standard 0.45-inch (11.43mm) semi-automatic pistol or revolver pistol. These requirements are actually similar to the popular concept of personal self-defense weapon (PDW).

This request of the US Army was put on hold for some time, and then it was put forward in 1940. The specific tactical and technical requirements put forward by the Ordnance Department of the United States Army are: the mass is less than 2.5kg, which can be used for single or continuous firing, and can replace pistols and submachine guns as the basic weapons used by noncommissioned officers, grass-roots officers or gunners, gunners, signalmen or second-line personnel. 1940 On June 15, the US Secretary of Defense officially approved the research and development of light self-defense weapons. 10 In mid-October, the US Army commissioned Winchester Company to develop a new type of bullet, the power of which is between rifle bullet and manual bullet. New guns are developed and produced by Winchester Company, Colt Company and Smith-Wei Sen Company, among which 1 1 Company.

Winchester, which is in charge of ammunition development, was busy adjusting the production line of M 1 Garland rifle, so it failed to submit the products in time in the first comparative test of 194 1 May. After the initial shooting test in May, the US Army gave up the requirement of continuous shooting. Winchester handed in their semi-automatic light weapons before the second comparative test in September. 194 1 On September 30th, 2008, the report of the selection committee considered that the sample gun of Winchester Company was the most suitable. The design scheme was formally finalized in June 194 1 10, and named as "M 1 0.30 inch (7.62mm) carbine".

The development team of M 1 carbine is led by edwin Bagsley, director of Winchester Institute. He invited david marshall Williams of North Carolina from outside the company, who was once considered as a genius designer who designed carbine in 13 days, and even called "carbine Williams".

Comparing several variant guns, the prototype M 1 carbine has the largest output, and * * * produces 55 1 1,000 guns. Compared with the M 1 Garland rifle, the magazine of the M 1 carbine rifle is easy to replace, the ammunition capacity is larger, the actual firing rate is higher, the recoil is lower, and the firing accuracy and penetration are better than those of the submachine gun using hand ammunition. Increasing the M2 firepower of the speed machine and the large-capacity magazine are "almost" equivalent to assault rifles (the reason for using "almost" is that its effective range is still too close). Therefore, during World War II, M 1 carbine and its variant guns were quite effective infantry melee weapons.

design feature

The 0.30-inch M 1 carbine ordinary bullet used in the M 1 carbine is manufactured by Winchester Company on the basis of the 0.32-inch (7.65mm) rifle bullet, and its external dimensions are slightly changed. The M 1 carbine ammunition adopts a straight cylindrical shell without flange and an arc warhead, with a mass of 7. 1g and a muzzle velocity of 570 m/s. The muzzle kinetic energy is about twice that of a 0.45ACP pistol, but only13 of a 0.30-06 rifle. Rifle, but the muzzle kinetic energy is too small and the warhead shape is not good, so its effective range is only about 200 m m, but in any case, its range is much farther than that of pistol, and its recoil is moderate. Besides M 1 ordinary bullets, M 16 and M27 tracer bullets and M6 blank bullets can also be used.

The M 1 carbine is designed by david walliams and adopts the principle of short-stroke piston automatic air guide. The air guide hole is located in the middle of the barrel, which is 1 15mm away from the front of the barrel, and the piston is below the barrel, with a recoil distance of only 3.5 mm When launching, gunpowder gas enters the air guide chamber through the air guide hole to push the piston to move backwards, and the piston impacts the gun rack to recoil. When the bolt seat returns to about 8 mm, the bore pressure drops to a safe value, which is the mechanical insurance before unlocking. Then, the bent section of the guide groove of the bolt holder is buckled with the bolt guide projection, and the bolt starts to rotate (and at the same time plays the role of pre-extracting the shell) to unlock. In the recoil process of the bolt, the shell hook on the bolt pulls the shell back, and after the shell is pulled out of the bore, it is thrown to the right front by the elastic shell thrower on the bolt.

When the rear end of the inertia body of the bolt holder hits the shell, the bolt holder stops recoil, and the bolt will not stop moving until it hits the rear end of the bolt through hole in the shell. At this time, the recoil stroke of the bolt is greater than the full length of the bullet, so the uppermost bullet in the magazine is sent to the ammunition supply position by the bullet support plate. Then the compressed recoil spring is stretched, the gun pusher is retracted, and the bullet is pushed into the gun chamber at the same time. Due to the interaction between the guide protrusion on the bolt and the guide groove of the bolt holder, the bolt rotates and realizes locking. Then the gun rack continues to retract until the front end of the inertial body pushes the piston into the piston barrel and stops completely. At this point, the gun is in a state of waiting to be hit again. In fact, the bolt of the M 1 carbine is basically the same as that of the M 1 Garland rifle, but the size is reduced in proportion.

When the striker moves forward, the protrusion at its tail end must enter the groove on the box beam, otherwise the striker cannot move forward. This can only be achieved after the bolt is rotated in place and locked. If the trigger is pressed when the bolt is not locked, the hammer will also rotate forward, but its energy is consumed to rotate the bolt to the locked position, so there is not enough energy to hit the needle and fire bullets, which can avoid accidents.

The manual safety in front of the trigger holder is directly pushed. When pushed to the left, the plane on the pin shaft of the safety device is aligned with the front end of the trigger, so that the front end of the trigger can fall and the shoulder at the rear end of the trigger can be raised. When the safety is pushed to the right, the cylindrical surface of the pin shaft of the safety machine moves below the front end of the trigger to prevent the trigger from moving down, thus forming the safety.

The safety switch on the early M 1 carbine was a horizontal push switch, but it was later changed to a rotary lever switch. This is because the safety button will soon overheat when shooting continuously, and the magazine button is next to the safety button, and the overheated safety button will affect the replacement of the magazine. M2 carbine can also be fired repeatedly. When the gun rack is put back in its original position, it hits the repeating rod, which lifts the iron block to release the hammer, and the gun fires continuously. The speed selector lever of M2 carbine is installed on the left side of the housing.

In the early M 1 carbine, the inverted L-shaped gauge was used, and the camera door was set to 150 yards (137m) and the small hole was set to 300 yards (274m). Later, both M 1 and M2 carbine changed the gauge to glide, and the distance can be adjusted from 100m to 300m, and the wind deviation can also be adjusted.

The earlier M 1 carbine was not equipped with a bayonet. Later, according to the requirements put forward by the army, the bayonet of M 1 carbine was tested in June, 2000. Finally, the T8 bayonet was selected in May 1944 and officially named M4 bayonet. At the same time, a square bayonet seat is added below the barrel.

The M 1 carbine is equipped with a grass-green canvas gun belt, and two magazine pockets can be attached to the stock to carry two spare magazines on the gun body. Both M 1 and M2 carbines can be equipped with M8 grenade launching sockets to launch grenades. IMI's Magal carbine is a mini galil deformation gun. Magel was originally designed to replace the M 1 carbine, which was born during World War II and is still widely used by the Israeli National Police and the Israeli National Guard. Israeli law enforcement agencies use M 1 carbine, mainly because the 5.56mm ammunition of M 16 and galil rifles is too penetrating in urban operations, and there are a large number of ammunition of M 1 carbine in Israel, so Magel's caliber is set to be the same as that of M 1 carbine. In order to transform the mini galil into a .30 caliber carbine, not only the barrel, bolt and magazine should be replaced, but also the air guide system should be modified accordingly, because the powder gas pressure of the 5.56 mm rifle bullet is much higher than that of the .30 carbine bullet. Besides, Magel can only be semi-automatic

In appearance, Magel and galil are also very different. Magel's shell and barrel are mostly wrapped in plastic, which can not only prevent the weapon parts from overheating and gunpowder gas from burning the shooter, but also prevent the weapon from being damaged by impact. According to the propaganda, the police can also use guns as batons. The lamp can also be installed on the plastic jacket under the bucket. If the plastic jacket is removed, the launching accessories for launching rubber riot bombs can be installed.

Magel was supposed to replace all M 16 used by the police, so IMI won 4,000 Magel production contracts. The original 65,438+0,000 yuan was delivered during the period of 65,438+0,999-2000 for the Israeli-Palestinian conflict in the occupied Palestinian territory. However, the user-Israeli police are not satisfied with the first batch of Magel, because the barrel of Magel is too short and the chamber pressure is too low, so that the action of the automatic mechanism fails from time to time, especially after assembling the accessories for launching riot bombs. Therefore, at the beginning of 200 1, all delivered Magel stopped using, and most of them were sent back to IMI for improvement.

IMI still provides the remaining 3,000 to law enforcement agencies, but only to the National Guard and ordinary police forces. Israeli police special forces still use M 16 gun families (mainly Colt Commandos and M4), and they do not intend to replace them with Magel in the future. IMI is also promoting this product to law enforcement agencies in other countries, and the unit price is about 1000 USD. M4A 1 carbine automatic shooting

M4 carbine is a product of American Colt Company, 199 1 came out, and it has been continuously improved since its service. M4 carbine weighs 3.4kg when carrying 30 rounds of magazines, which is 600g lighter than M 16A2. Its barrel is also 500mm； shorter than M 16A2; 80% parts of the basic M4 are the same as M 16A2, and the shooting mode is also semi-automatic and three-point shooting. So it is appropriate to say that it is a shortened M 16. The M4 enhancement is improved according to the requirements of the navy and can shoot automatically. The most eye-catching improvement is M4A 1. It has become the standard weapon of American special operations forces. M4A 1 is light. It uses M 19 13 tactical slide rail to replace the original grip, and can freely attach other devices, and is equipped with a built-in red dot sight and a tactical glare flashlight, which improves the night fighting ability and hit rate. It fires a 5.56 mm bullet. Because it can shoot automatically, it has strong firepower and close combat is very powerful.

The main difference between M4 and M4A 1 carbine is that the folding handle/gauge assembly of the latter is installed on the guide rail of M1L-STD-1913 standard Picardi, which can be used for both three-shot and fully automatic shooting like M4. Various optical sights and other accessories can be quickly installed on Picani's guide rail without zero adjustment.

M4 carbine changed the telescopic stock with only two fixed positions into four fixed positions, and then changed it into six. In addition, although the M4 photo gate is M 16A2, its size can only be adjusted to 600 meters at most, instead of 800 meters of M 16A2. Because the lower casing is M 16A2, its shooting mode is semi-automatic and three rounds. Because M4 and M 16A2 are very similar, in fact, 80% of their parts are interchangeable, so it was originally called M 16A2 carbine by some people. M4 was first equipped with the 82nd Airborne Division, which was used to replace the M16A1A2 rifle, M3A 1 submachine gun and 9mm pistols used by some vehicle drivers. 1994 officially installed. According to H&; K According to the information provided by American company official website, the development plan of HK4 16HKM4 (time-honored brand) began in 2002. When H &；; After improving the British SA80(L85/L86) weapon system, K Company began to evaluate the technical feasibility of improving the M 16 series carbine in early 2002, with the aim of improving the reliability and service life of the M 16 series weapons.

HK4 16 can be modified from the standard M 16A2/A4 upper shell, and only the air guide device, upper shell assembly, barrel and magazine are developed by HK Company. Its air guide system is an improved AR- 18 (piston type) air guide device. After the research work of G36 and improved SA80, the engineers of HK Company must be familiar with this air guide system. Before G36, almost all automatic weapons of HK Company adopted rolling locks, and after G36, almost all automatic weapons of HK Company also adopted AR- 18 air guide device. Engineers of Hong Kong companies do use mature technology. But in any case, this new type of air guide device is more reliable than the M 16 series air guide device which is easy to get dirty, and it can greatly reduce the maintenance times of users.

The air guide device of M 16 is air blowing type. It is to open an air guide hole on one side of the cylinder and connect the air guide pipe, which is connected by bolts. The working process is as follows: firing a bullet-the bullet passes through the air guide hole-some gas enters the air guide pipe, blowing-firing again to reset the bolt. Due to the characteristics of this air guide method, a large amount of carbon ash (residue after powder combustion) will enter the air guide pipe, block the air guide pipe, pollute the bolt machine, and the heat will also evaporate the gun oil, leading to the failure of the bolt machine.

In order to improve the service life, HK Company has made four kinds of cold forged barrels with different lengths, 10, 14.5, 16.5, 20 inches, all of which have a service life of more than 20,000 rounds. At present, there are four different lengths of barrels. In addition, a new buffer device is adopted to improve the reliability and safety of the weapon. In addition, a more reliable magazine has been developed (the 4 179 standard magazine used in M 16 often has the phenomena of ammunition replenishment failure, fire and so on). As can be seen from the above figure, H &；; K has also improved.

Carbine is a weapon used to make up for the lack of firepower in medium and close range.