RPK light machine gun
The development and use of weapons for one cartridge has greatly simplified the supply of ammunition to troops. At the beginning of the fifties, there was a proposal to continue the unification of the existing systems, this time through the creation of families of weapons. In 1953, the Main Artillery Directorate developed tactical and technical requirements for a new family of small arms chambered for 7,62х39 mm. The military wanted a complex consisting of a new machine gun and a light machine gun. Both samples should have the most similar design using common ideas and details. The technical assignment implied that the new “lightweight” machine gun in the near future would replace the existing AKs in the troops, and the machine gun unified with it would become a substitute for the existing RPDs.
The competition for the creation of a new shooting complex was attended by several leading gunsmiths. V.V. Degtyarev, G.S. Garanin, G.A. Korobov, A.S. Konstantinov and M.T. Kalashnikov. The latter submitted to the competition two types of weapons, which were subsequently put into service under the names AKM and PKK. The first tests of the proposed weapons were held in 1956 year.
Testing and refinement of the proposed machines and machine guns continued until the 1959 year. The result of the first stage of the competition was the victory of the Kalashnikov assault rifle. In 1959, the AKM assault rifle was adopted by the Soviet Army, which to some extent predetermined the choice of a new light machine gun. The Kalashnikov machine gun itself was put into service two years later. During this time, the designer has improved its design and, while maintaining the necessary degree of unification, brought the characteristics to the desired level.
At the request of the customer, the new light machine gun had to repeat as much as possible the design of the machine gun being developed simultaneously with it. As a result, the PKK designed by M.T. Kalashnikov in many of its features resembled an AKM machine gun. Naturally, the design of the machine gun provided some differences related to its intended use.
The PKK machine gun was built on the basis of gas automation with a long piston stroke. This scheme has already been worked out in the AK project and without significant changes passed to AKM and PKK. In terms of the overall layout of assemblies and assemblies, the new machine gun did not differ from the existing and prospective machine guns either.
The main part of the RPK machine gun was a rectangular receiver. For access to the internal units provided a removable lid with a latch in the back. In front of the receiver was attached barrel and gas tube. The experience of using the RPD and other similar weapons showed that the new light machine gun could do without an interchangeable barrel. The fact is that a heavy barrel with relatively thick walls did not have time to overheat even during the use of all portable ammunition. To increase firepower in comparison with the base automatic, the PKK machine gun received a barrel with a length of 590 mm (415 mm for AKM).
Directly above the barrel was a gas tube with a piston. The middle part of the receiver was set aside for the shutter and fixing units of the magazine, the back part - for the trigger mechanism. A characteristic feature of the PKK machine gun has become an updated barrel box. She almost did not differ from the corresponding parts of the machine, but had a reinforced structure. The box and the lid were stamped from steel sheet, which simplified production compared to milled units of AK automatons.
All parts of automation without changes were borrowed from the base machine. The main element of the gas engine was a piston rigidly connected to the bolt carrier. Locking the barrel before the shot was made by turning the shutter. When moving forward, during the filing of the cartridge in the chamber, the bolt interacted with the shaped groove on the bolt carrier and rotated around its axis. In the extreme forward position, it was fixed with the help of two lugs that fit into the corresponding grooves of the receiver liner. The backframe of its rear part is in contact with the return spring, located directly under the receiver cover. To simplify the design, the shutter handle was part of the bolt carrier.
Requirements for the life of the barrel and various parts of automation led to the need to use chrome. The coating received the barrel bore, the inner surface of the chamber, the piston and bolt stem. Thus, protection received parts in direct contact with the powder gases that can cause corrosion and destruction.
In the back of the receiver was a trigger mechanism trigger type. In order to preserve the maximum possible number of common parts, the PKK machine gun received trigger with the possibility of firing single and in automatic mode. The flag of the fuse-translator of fire was located on the right surface of the receiver. In the raised position, the flag blocked the trigger and other parts of the trigger and did not allow the slide frame to move. In view of the continuity of the design, the shot was made from the front sear, with the patron drilled out and the barrel locked. Despite the fears that existed, the thick barrel and the shooting, mostly in short bursts, did not allow spontaneous firing to occur due to overheating of the liner.
For ammunition, the PKK machine gun was supposed to use several types of shops. The unification of the design with the AKM assault rifle made it possible to use the existing sector stores on 30 cartridges, but the need to increase the firepower of the weapon led to the emergence of new systems. Kalashnikov light machine guns were completed with two types of stores. The first is a two-row sector on 40 cartridges, which was a direct development of the automatic magazine. The second store had a drum structure and contained 75 cartridges.
Inside the drum casing, a spiral guide was provided along which the cartridges were located. In addition, when equipping such a store, the machine gunner had to cock a spring-loaded cartridge feed mechanism. Under the action of the cocked spring, a special pusher guided the cartridges along the guide and pushed them to the neck of the store. A characteristic feature of the drum mechanism were certain difficulties with his equipment. This process was more complicated and took longer than working with the sector store.
For aiming the shooter had to use the front sight mounted above the barrel muzzle and an open sight on the front of the receiver. The sight had a scale with divisions from 1 to 10, which allowed firing at a distance of up to 1000 m. It was also possible to make lateral corrections. By the time of adoption of the new machine gun was mastered the production of devices for shooting at night. It consisted of an additional pillar and front sight with self-luminous dots. These parts were mounted on top of the base sights, and, if necessary, could recline, allowing you to use the existing rear sight and front sight.
Ease of use of the PKK machine gun was provided by the presence of several wooden and metal parts. To hold the weapon should use a wooden forearm and pistol grip. In addition, a wooden butt was attached to the receiver. The form of the latter was partially borrowed from the RPD machine gun available to the troops. When shooting lying down or with an emphasis on bipods on any object, the machine-gunner could hold the weapon by the thin neck of the butt with his free hand, which positively affected the accuracy and accuracy of fire. Behind the mounts flies on the trunk located mount bipods. In the transport position, they were folded and placed along the trunk. In the unfolded position, the bipods were held by a special spring.
Light machine gun design M.T. Kalashnikov turned out significantly larger and heavier than the unified machine gun. The total length of the weapon reached 1040 mm. The weight of a weapon without a magazine was 4,8 kg. For comparison, the AKM machine gun without a bayonet had a length of 880 mm and weighed (with an empty metal magazine) 3,1 kg. The metal magazine on the 40 cartridges weighed around 200 g. The weight of the drum magazine reached 900 g. It should be noted that the PKK with ammunition was noticeably lighter than its predecessor. The PKK with the equipped drum magazine weighed about 6,8-7 kg, whereas the RPD with the tape without cartridges pulled on the 7,4 kg. All this increased the mobility of the fighter on the battlefield, although it could affect some of the combat characteristics of the weapon.
The developed automation, borrowed from the existing sample, allowed to achieve the rate of fire at the level of 600 rounds per minute. Practical rate of fire was less and depended on the mode of trigger control. When shooting single per minute, it was possible to make no more than 40-50 shots, with automatic fire - up to 150.
With the help of a trunk of increased length, it was possible to bring the initial velocity of the bullet to 745 m / s. The target range was 1000 m. The effective range of ground targets was smaller - 800 m. From a distance of 500 m, it was possible to conduct effective fire on flying targets. Thus, the majority of the fighting qualities of the PKK machine gun remained at the level of the RAP in the army. At the same time there were significant gains in weight and unification of the structure with an automatic machine. Requirements for the normal combat machine guns PKK and RPD were the same. When shooting with 100 m at least 6 from 8 bullets had to fall into a circle with a diameter of 20, see. The deviation of the midpoint of impact from the aiming point could not exceed 5, see.
RPX machine gun
Simultaneously with the PKK light machine gun, its collapsible version of the PKSC was developed, designed for airborne troops. Its only difference from the basic design was a folding butt. To reduce the length of the weapon to 820 mm, the butt folded to the left and fixed in this position. The use of a hinge and some related parts led to an increase in the weight of the weapon by about 300.
Later came the "night" modification of the machine gun. The RPKN product differed from the basic version by the presence of a mount on the left side of the receiver, on which any suitable night sight could be mounted. With the RPK machine gun, the NSP-2, NSP-3, NSPU and NSPUM sights could be used. As the sights developed, the target detection range increased, although even the most advanced night sights did not allow for firing at the maximum possible distance.
The Kalashnikov light machine gun was adopted by the Soviet Army in 1961. Serial production of new weapons was deployed at the Molot plant (Vyatskiye Polyany). Machine guns were massively supplied to the troops, where they gradually replaced the existing RPD. The light machine guns of the new model were a means of reinforcing motorized rifle squads and, from the tactical niche point of view, were a direct replacement for the existing RPDs. The complete replacement of obsolete weapons took several years.
Having provided its own weapon with its own army, the defense industry began to export it. Approximately in the mid-sixties, the first batches of PKK machine guns went to foreign customers. Soviet-made machine guns were supplied to more than two dozen friendly countries. In many countries, such weapons are still used and is the main machine gun in the army.
Some foreign countries have mastered the licensed production of Soviet machine guns, and also developed their own weapons based on the purchased PKK. Thus, in Romania, the Puşcă Mitralieră model 1964 machine gun was produced, and Yugoslavia from the early seventies collected and used the Zastava X72 products. The Yugoslav specialists further modernized their development and created the M72B1 machine gun. In 1978, the Yugoslavs sold the license for the production of the M72 to Iraq. There this weapon was produced in several versions. There is information about their own modernization projects.
In the sixties, Vietnam became the most important customer of the PKK machine guns. The Soviet Union supplied at least several thousand such weapons to friendly troops that participated in the war. The establishment of relations between the USSR and many developing countries in Asia and Africa, among other things, led to the use of PKK machine guns in a multitude of armed conflicts on several continents. This weapon was actively used in Vietnam, Afghanistan, in all Yugoslav wars, as well as in many other conflicts, up to and including the civil war in Syria.
In the early seventies, Soviet gunsmiths developed a new intermediate cartridge 5,45х39 mm. The military decided to make it the main ammunition for small arms, for which several new assault rifles and machine guns were developed. In 1974, the AK-74 submachine gun and the RPK-74 light machine gun of MT design were adopted. Kalashnikov using a new cartridge. The transfer of the army to the new ammunition affected the further fate of the existing weapons. Outdated AK assault rifles and PKK machine guns were gradually replaced by new weapons and sent for storage, disposal or export. However, the replacement of old weapons lasted for a long time, which affected the timing of its operation.
The Kalashnikov PKK light machine gun became an important milestone in stories development of modern domestic small arms. With the help of this machine gun the serious question of the unification of various rifle systems was resolved. By using common ideas and some unified nodes, the authors of the project managed to significantly simplify and cheapen the production of weapons while maintaining the characteristics at the level of the existing RPD. This was the main advantage of the new machine gun.
However, the PKK machine gun was not without flaws. The first thing to note is the reduction in ready-to-use ammunition. The RPD machine gun was completed with 100 ammo tape. Included with the PKK there was a sector store on 40 and a drum cartridge on 75 cartridges. Thus, without replacing the magazine, the shooter could have made at least 25 fewer shots. At the same time, however, it took less time to replace the store than to refill a new tape.
Another disadvantage of the PKK machine gun was related to the automation used. Most machine guns fire from the open bolt: before the shot, the bolt is in the rearmost position, which, among other things, improves the cooling of the barrel. In the case of the PKK, the sending of the cartridge into the chamber occurred before pressing the trigger, and not after, as is the case with other machine guns. This feature of the weapon, despite the heavy barrel, limited the intensity of shooting and did not allow to shoot in long bursts.
PKK machine guns were actively used by the Soviet army for several decades. Some armies use this weapon until now. Despite its age, these weapons still suit the military in many countries. You can argue about the pros and cons of the Kalashnikov light machine gun for a long time, but the half-century history of operation speaks for itself.
On the materials of the sites:
http://world.guns.ru/
http://gunsru.ru/
http://spec-naz.org/
http://kollektsiya.ru/
http://russianguns.ru/
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