Underbarrel flamethrower. Indispensable "grenade launchers"

The Soviet Union became interested in under-barrel grenade launchers in the 60s, after information was received about the successful use of the XM148 model with an under-barrel grenade launcher during the conflict in Vietnam. Military leadership made several orders, and several prototypes were constructed by various design bureaus. But they did not have the necessary operational and technical characteristics. This is how the under-barrel grenade launcher for the machine gun appeared - GP-25

Creation of GP-25

To create a single model of this kind, in 1971, the design bureaus of the entire Union were given the appropriate task. The project was called "OCR "Bonfire"". Tula Design Bureau, which developed hunting and military weapon, entrusted this task to V.N. Telesh, since he already had similar experience behind him. He set to work together with engineers from the Pribor State Research and Production Enterprise in Moscow. The result of this work was the adoption in 1978 of the GP-25 Koster under-barrel grenade launcher. It was prescribed to be used in conjunction with AKM and AKMS assault rifles. When the grenade launcher appeared, it received the GRAU 6G15 index.

However, they began to supply the army en masse only in 1980, when the USSR fought in Afghanistan. As the experience of the first few months of fighting showed, the troops really needed such weapons as an under-barrel grenade launcher.

General characteristics

GP-25 "Bonfire" is designed to destroy enemy personnel who are located in open areas or in shelters (trenches, trenches), and, thus, cannot be hit from conventional small arms.

Weapons to which the under-barrel grenade launcher can be attached are AK-74, AKM, AKMS and AKS-74U in 7.62 or 5.45 mm caliber. How does the entire structure work when assembled? In this case, depending on the current situation in battle, it is possible to fire from both a machine gun and a grenade launcher.

Weapon design

GP (under-barrel grenade launcher) consists of the following parts:

a barrel on which there are sighting devices and a bracket for attaching the grenade launcher to the weapon;
breech;
trigger mechanism with housing and handle;
the actual grenade launcher is automatic.

The standard equipment of the grenade launcher includes the following items:

the grenade launcher itself;
carrying bag;
bag for grenade launcher shots;
rubber butt plate and belt;
banner

The weapon has a fairly long (205 mm) barrel, in which there are 12 screw rifling (right-handed). In order to load the weapon, a grenade is inserted into the barrel, which is held inside using a special lock. If necessary, it can be removed back - for this purpose a special extractor has been invented with a key that needs to be pressed with your finger.

There is a bracket with a guard to attach the weapon to the machine gun. To attach a grenade launcher to an AK, it is enough to attach the bracket from below to the forend, and the latch itself will fix it in a secure position. There is a spring shock absorber on the bracket at the front.

The weapon has a self-cocking trigger mechanism. The principle of its operation is quite simple. Pressing the straight trigger pulls the hammer back using a special hook, while the mainspring is also compressed. If you press the trigger further, the trigger will come off the hook. At the same time, it acts on the firing pin, which breaks the capsule of the shot grenade.

There is also a fuse located on the right side of the barrel. There are two modes - “PR” (fuse) and “OG” (fire). There is also another protective system: if the grenade launcher is incorrectly attached to the machine gun, the shot will not be fired. In both cases the trigger is securely locked.

Sights

The sighting devices available on the grenade launcher allow both direct and semi-direct fire. They are mounted on the left side of the bracket, the distance scale is made in the form of an arc. If direct fire is necessary, then aiming is done through the front sight and folding rear sight. The range can be adjusted. To do this, the cam moves the front sight back and forth, so you can make corrections for the derivation of the grenade. To fire through semi-direct fire, two factors need to be taken into account - direction and range. Aiming for the first is carried out through the rear sight and front sight, and for the second - through a plumb line and a distance scale (similar to the “quadrant” method). But the peculiarity of semi-direct fire is that it is needed only for mounted shooting.

The maximum range at which the GP-25 underbarrel grenade launcher is capable of accurate shooting is 400 meters. Firing range (subject to mounted fire) is approximately 200 meters. However, the accuracy of fire is quite high. At a distance of 400 meters, the grenade deviates in range by no more than 6 meters, and along the front this figure is 3 meters. It must be taken into account that side winds have a great influence. To do this, you need to adjust the front sight by shifting it.

Safety and convenience when shooting

Since the under-barrel grenade launcher has much greater recoil than that of an assault rifle, devices are provided that allow firing with comfort for the shooter. A universal rubber butt pad is attached to the butt, and its features are such that it can be adapted both to butts made of wood and plastic (like AK-74 or AKM), and to folding butts of AKMS or AKS-74 assault rifles. The grenade launcher body softens its impact on the fore-end, and its insert protects the receiver from impacts.

Tests in the field revealed an unpleasant feature - when fired, the receiver cover, which is usually secured with the head of the return spring rod, often flew off. Therefore, a special rod was developed, the design of which included a hook. When installing a grenade launcher, the standard rod is replaced with it. In the design of the AK-74M assault rifle, this feature has become standard, that is, all such weapons are produced with a modified rod.

Ammunition and shooting

The GP-25 grenade launcher fires VOG-25 and VOG-25P rounds, as well as their improved versions - VOG-25M and VOG-25PM. They all have fragmentation grenade, which is equipped with an instantaneous fuse with a self-liquidator.

Characteristics of the VOG-25 shot:

grenade weight - 250 g;
weight - 48 g;
The radius of damage from fragments is 6 meters.

The standard ammunition load is 10 grenades, they are carried in a bag that comes with the grenade launcher. It consists of two cassettes made of matter, each holding 5 ammunition. The peculiarity of wearing such a bag is that no matter what position the shooter is in, the cassettes are always within reach. In addition, many safety vests used in modern army, have sockets for carrying rounds for the GP-25.

You can shoot from any position - even standing, sitting, or kneeling. Every soldier is taught how to fire an under-barrel grenade launcher correctly. Direct fire shooting at distances of up to 200 meters is carried out with the butt of the machine gun resting on the shoulder, and at longer distances - “from under the hand”, that is, the butt is placed under the shooter’s arm. If you need to shoot at targets shielded from direct fire, the machine gun rests its butt on the ground.

Since the grenade of an underbarrel grenade launcher has a low initial speed, shooting at angles is quite convenient - the shot is less blown away by the wind, the trajectory is not so steep and the flight time is reduced. However, when there is a headwind, it is dangerous to open fire from a grenade launcher.

Some features

As you might guess, the grenade launcher weighs down the machine gun it is attached to. A fully equipped AK-74 with GP-25 weighs approximately 5.1 kg. However, this is only beneficial. The center of gravity of the weapon shifts forward and down, that is, if you attach an under-barrel grenade launcher, the AK-74 begins to “lower.” Therefore, the shooter will need certain time to get used to the changes in your weapon. However, with the proper level of skill, you can significantly increase the accuracy of a machine gun’s fire, since the weight prevents it from “throwing” in different directions.

In departments

According to the regulations, the modern one is equipped with two assault rifles with GP-25, in addition to conventional AKs. In the conditions of modern tactics and methods of warfare, this makes even the smallest unit quite independent, because an assault rifle with an under-barrel grenade launcher plays the role of assault weapons, thereby making it easier for your unit to solve certain tasks in battle.

Weapon variants and modifications

Since the GP-25 under-barrel grenade launcher also entered service with the troops of the Ministry of Internal Affairs of the Russian Federation, the question arose of how to turn it into a non-lethal weapon. And it was resolved quite quickly. The main changes, of course, affected the ammunition. A special “Nail” cartridge has been developed for the grenade launcher, which is equipped with a non-standard fragmentation grenade, but the same, but filled with poison gas type CS. The characteristics of such a shot are as follows:

weight - 170 g;
maximum shot range - 250 m;
minimum shot range - 50 m;
time of complete gas release - 15 seconds;
cloud volume - 500 m3.

Original idea originated from the designers of the Research Institute of the Ministry of Internal Affairs. It was decided to adapt the GP-25 for firing ammunition from the KS-25 carbine - with gas, rubber or plastic bullets. For this purpose, a special removable barrel with a caliber of 23 mm was developed. This system is called "Larry".

In addition to standard models, a modified version is also produced - GP-30. This is the same GP-25 underbarrel grenade launcher, only lighter, and its sighting devices are located on the right side. There is also a modification for export - GP-30U, which is intended for use with foreign assault rifles.

Underbarrel grenade launcher GP-25 - technical characteristics

So, the characteristics:

caliber - 40 mm;
total length - 323 mm;
barrel length - 205 mm;
total width - 76 mm;
height - 120 mm;
weight (without butt plate) - 1.5 kg;
maximum firing range (sighting) - 400 m;
rate of fire - 4-5 rds/min;
ammunition - 10 shots;
the initial speed of the grenade is 76 m/sec.

The GP-25 Koster under-barrel grenade launcher is in service with the Russian Army, as well as a number of armies of other countries to this day. It gained its popularity due to its reliability, convenience and good tactical and technical characteristics.

The publication brought to the attention of readers represents one of the first successful attempts to give an objective picture of the development in our country of this type of individual automatic weapons, such as machine guns. Until now, most significant facts and events of interest for historical analysis have been classified. The book “The History of the Russian Automatic Machine” was prepared on the basis of the author’s work with a significant number of domestic and foreign sources, including previously inaccessible documentary and archival materials from the Ministry of Defense and the Ministry of Defense Industry. Therefore, it will be very useful as an objective historical research not only to specialists in the field of close combat weapons, but also to a wide range of readers interested in the history of small arms, their present and future.

Note OCR: The publication is also interesting because it describes in detail all the models of small arms submitted to competitions, the advantages and disadvantages, the testing procedure, and removes many of the myths that have accumulated in this area.

CHAPTER 3 Creation of an automatic grenade launcher system

Simultaneously with the creation of a new machine gun, work was carried out in the Soviet Union to expand its functions. Using previously developed R&D skills. in 1975 to expand the fire capabilities of the shooter and increase the density of fire from motorized rifle and airborne units designer TsKIBSOO V.N. Telesh, in cooperation with the designers of the Moscow State Research and Production Enterprise “Pribor”, began to create a powerful means of close combat at distances of up to 400 m. The theme of the development work was given the code “Bonfire”. As a result of these works, an automatic grenade launcher system was created, consisting of a 5.45 mm AK74/AKS74 assault rifle and a muzzle-loading 40 mm grenade launcher (index 6P5) mounted under its barrel. Along with the AK74, the 6G15 grenade launcher could also be mounted on 7.62 mm AKM/AKMS assault rifles. After successful tests in 1978, an under-barrel grenade launcher, designated GP-25, was put into service, and the following year, 1979, their large-scale production began at the Tula Arms Plant.

The GP-25 underbarrel grenade launcher, being the shooter’s individual weapon, was intended for open destruction. as well as enemy personnel hiding in trenches, trenches and on the reverse slopes of heights.

For firing from a grenade launcher, 40-mm unitary VOG-25 rounds (index 7P17) with a fragmentation grenade equipped with an instantaneous head fuse with a self-destructor were initially used. The propellant charge, together with the ignition agent, was located in the bottom of the grenade body, which significantly simplified loading the grenade launcher and also increased its rate of fire. The body of the grenade has ready-made rifling that serves to give the grenade rotational movement in the bore, since it is stabilized in flight due to rotation. The length of the VOG-25 shot is 103 mm. The initial flight speed of the grenade is 76 m/s. Shot weight - 0.255 kg. The mass of the explosive explosive charge is 0.048 kg.

In 1979, the ammunition load of the GP-25 grenade launcher was expanded; in addition to the VOG-25, another 40-mm shot was received - the VOG-25P (index 71124), created on the theme of the OCD - Foundling -. It differed from its predecessor in the new VMG-P head fuse with an expelling charge and a pyrotechnic substitute, which ensured bouncing of the grenade after it hit the ground and detonation in the air at a height of 0.75 m when firing at all ranges combat use underbarrel grenade launcher. Such a design solution of the new ammunition made it possible to increase the effectiveness of fragmentation action compared to the VOG-25: in terms of open enemy manpower - by 1.7 times, and in terms of enemy manpower hiding in trenches and trenches - by 2 times. The length of the VOG-25P shot is 125 mm. The weight of the VOG-25P shot is 0.275 kg. The mass of the explosive explosive charge is 0.042 kg.

The GG 1-25 grenade launcher consists of three parts: a barrel with sighting devices and a bracket for mounting the grenade launcher on a machine gun, a breech and a trigger mechanism housing with a handle. The grenade launcher kit includes: a rubber butt with a belt, a return spring guide rod with a latch (for installation on a machine gun), a bag for carrying the grenade launcher, two bags in the form of fabric clips with sockets for 5 shots each, and a banner for cleaning and lubricating the barrel.

The grenade launcher was connected to the machine gun using a special bracket, fixed in a certain position on the barrel with a latch. The trigger mechanism of a self-cocking grenade launcher. It is equipped with a blocking device, thanks to which it is impossible to fire from a grenade launcher that is not attached or not completely attached to the machine gun, as well as when the shot is not completely sent into the barrel. In addition, the grenade launcher is equipped with a safety gel that prevents accidental shots. The frame of the body covers the forend of the machine gun and protects it from mechanical damage when firing. An elastic insert is glued into the frame, softening hard blows to the receiver of the machine gun when firing from a grenade launcher. For firing from a grenade launcher, the Service Manual for the entire period of its operation, together with the machine gun, prescribes replacing the standard guide rod of the return spring in the machine gun equipped with the GP-25. and install a new rod with a latch included in the grenade launcher kit. It serves to prevent spontaneous detachment of the receiver cover from the machine gun during firing from a grenade launcher. A spring-loaded latch, jumping over the edge of the hole in the receiver cover, keeps it from possible longitudinal inertial movement back when firing. However, the dynamic nature of the efforts and stresses experienced by machine guns when firing from a grenade launcher mounted on it. despite all the measures taken is significant. Therefore, when the grenade launcher reaches more than 400 shots, the machine gun on which the GP-25 is installed is removed from service along with the grenade launcher and can be used further for its intended purpose, but without the grenade launcher.

The grenade launcher is loaded from the muzzle of the barrel. The tail part of the shot is inserted into the barrel of the grenade launcher and moves all the way into the breech. In this case, the latch slides into the locking groove and holds it in the barrel bore. When fired from a grenade launcher, the firing pin pierces the grenade's igniter cap, which in turn initiates a powder propellant charge. Under the influence of powder gases, the translational and rotational movement of the grenade begins with the simultaneous arming of the VMG-K fuse. Cocking is completed after the grenade leaves at a distance of 10 to 40 m from the muzzle of the barrel. When it encounters an obstacle, a fuse is triggered, detonating the explosive charge placed in the grenade body. If the fuse fails to function due to the reaction-inertia mechanism, when it encounters an obstacle, after 14 seconds the grenade is detonated by the self-destruction mechanism of the fuse. An unused shot is removed from the barrel using a special extractor.

Firing from an under-barrel grenade launcher is usually carried out alternating with firing from a machine gun. Sighting device open type installed on the left wall of the bracket. On the same foam there is a distance scale. For direct fire at a visible target, a folding rear sight and front sight are used. In this case, grenades are fired along a flat trajectory from an automatic grenade launcher system at a distance of up to 200 m with the butt resting on the shoulder; for this, the butt of the machine gun is equipped with an additional rubber butt pad, which softens the rather strong recoil. Aiming is carried out directly at the target or at a point in the target area. The sight is fixed using a trellis type mechanism. When firing along a mounted trajectory with elevation angles up to 80° (from closed positions at unobserved targets) at ranges from 100 to 400 m, fire is carried out using a remote scale for remote shooting (at barrel elevation angles of more than 45°) and a plumb line suspended on sight axis; with the butt clamped under the shooter's arm, or with the butt of the machine gun resting on the ground. Moreover, to fire at minimum ranges (100 m), a crane device was initially used in the design of the grenade launcher. However, military tests revealed that this device was irrational, so in subsequent series it was removed, and the minimum range for mounted firing was increased to 200 m. The grenade launcher is aimed at the target in the direction of the target, and the required elevation angle is given to the grenade launcher barrel along a plumb line. In this case, the barrel grenade launcher plays the role of a mortar. The combat rate of fire of the GP-25 grenade launcher reaches 4–5 rounds per minute. The length of the grenade launcher is 323 mm. The length of the rifled part of the barrel is 98 mm.

Weighing only 1.5 kg, the GP-25 Koster grenade launchers have been significantly expanded combat capabilities machine gun to destroy enemy personnel with shrapnel within a radius of 5 m at ranges from 150 to 400 m. The armament of two riflemen in the motorized rifle squad with under-barrel grenade launchers significantly influenced the expansion of the infantrymen's fire capabilities. The experience of combat operation of the GP-25 in Afghanistan revealed certain shortcomings in the design of the grenade launcher, including the ineffectiveness of firing at invisible targets due to the inability to adjust fire and the small portable ammunition load (10 shots). Therefore, in 1985–1988. Tula designers carried out significant development work, known as the “Shoe” theme, aimed at modernizing the under-barrel grenade launcher. Their result was new model 40-mm underbarrel grenade launcher GP-30 (index 6G21). which was put into service in 1989. Structurally similar to the GP-25, the new grenade launcher differed from its predecessor primarily in the labor intensity of manufacturing reduced by 30%. a new sight design, excluding the safety lever and reduced weight to 1.2 kg. A simpler mechanical quadrant sight (from which the plumb line was excluded) was moved to the right side of the machine gun’s aiming line. This made it possible to improve the operational characteristics of the entire complex. Since the shooter will now tilt his head towards the butt rather than to the left of it, aiming the grenade launcher has become much more convenient. It immediately became more convenient to carry a Kalashnikov assault rifle with a GP-30 grenade launcher in the “on the belt” position. In addition, moving the sight to the right side made it possible to reduce the possibility of mechanical damage to the sight when the shooter moves by crawling.

Performance characteristics
Caliber, mm
Shots used	VOG-25, VOG-25P
Length, mm
Length of the rifled part of the bore, mm
Weight of the grenade launcher without butt plate, kg
Initial speed of grenade flight, m/s	76
Combat rate of fire, rds/min
Maximum firing range, m
Minimum mounted firing range, m

After the M203 underbarrel grenade launcher appeared in service with the US Army, our military had a belated desire to have something similar.
The development of an under-barrel grenade launcher to expand the combat capabilities of infantry began in the USSR in 1975. The development was based on the experience gained in the second half of the 1960s when creating experimental under-barrel grenade launchers on the Iskra theme.

In 1978, the GP 25 “Koster” underbarrel grenade launcher (index 6G15), created at TsKIB SOO V.N., was put into service. Telesh for use in combination with AKM, AKMS, AK 74 and AKS 74 assault rifles. The production of the grenade launcher was established by the Tula Arms Plant.
GP 25 has a simple device and belongs to the muzzle-after-in-line rifled systems. The caliber fragmentation round VOG 25 or VOG 25P developed by State Research and Production Enterprise "Pribor" combines a grenade and a propellant charge in a cartridge case and is inserted into the barrel without effort, entering the rifling of the barrel with 12 protrusions of the leading belt, and is held in the barrel under a spring lock.
The grenade launcher has a hammer-type self-cocking trigger mechanism with a safety lever that locks the trigger. The grenade launcher is mounted on the forend of the machine gun with a bracket with a guard and secured with a latch. To soften the impact of recoil on the shooter and the weapon, a rubber butt plate is attached to the butt, the frame of the GP 25 trigger mechanism body protects the forend of the machine gun from damage, and the elastic frame insert softens the blow to the receiver.
The accessory includes a return spring rod with a hook, which replaces the usual guide rod of the machine gun to prevent the receiver cover from being torn off when fired from a grenade launcher.
The quadrant mechanical sight is designed for direct or semi-direct fire; a correction for grenade elevation is automatically introduced. At a distance of 400 m, the median hit deviations are 6.6 m at range and 3 m at the front. Together with AKM and AK 74 assault rifles, the GP 25 formed a successful, compact and easily controlled automatic grenade launcher system. Direct fire is usually fired: at a distance of up to 200 m - with the butt resting on the shoulder, 200-400 m - with the butt pressed under the arm, and along a steep upward trajectory - with the butt resting on the ground.

Since the early 1970s, in the Soviet Union, simultaneously with the creation of the new 5.45 mm Kalashnikov AK-74 assault rifle, full-scale work was carried out to expand its functions. Using the previously developed development work (R&D), in 1972, in order to expand the fire capabilities of the shooter and increase the density of fire of motorized rifle and airborne units, Tula designer TsKIBSOO V. N. Telesh, in cooperation with engineers from the Moscow State Scientific and Production Enterprise "Pribor", began to create a new powerful close combat weapon at distances up to 400 meters. The theme of the development work was coded “Bonfire”. As a result of these works, an automatic grenade launcher system was created, consisting of a 5.45-mm AK-74/AKS-74 assault rifle and a muzzle-loading 40-mm grenade launcher (index 6 G15). Along with the AK-74, the 6 G15 grenade launcher could also be mounted on 7.62 mm Kalashnikov AKM/AKMS assault rifles. After successful tests in 1978, the under-barrel grenade launcher, named "GP-25", was put into service Soviet army, and already the next year, 1979, the Tula Arms Plant mastered its mass production.

In combat, Kalashnikov assault rifles equipped with GP-25 grenade launchers can serve as both fire support and “assault” weapons. Since, with an under-barrel grenade launcher attached to the machine gun, the machine gunner, depending on the task at hand, can fire from both the under-barrel grenade launcher and the machine gun.

The GP-25 under-barrel grenade launcher, being an individual weapon of the shooter, is intended to destroy open enemy personnel, as well as those hiding in trenches, trenches and on the reverse slopes of heights. The GP-25 grenade launcher has a relatively low mass and small dimensions with sufficient long range shooting. In terms of rate of fire, it is significantly superior to all other single-shot grenade launchers due to the absence of the need to remove spent cartridges, open and close the bolt, or cock the hammer.

The GP-25 under-barrel grenade launcher consists of three parts: a barrel with sighting devices and a bracket for attaching the grenade launcher to the machine gun; the breech and the body of the trigger mechanism, on which the pistol grip is attached, ensuring ease of shooting. To be carried in the stowed position, the grenade launcher is disassembled into two parts: one is the barrel, the other is the breech and the housing of the trigger mechanism. The grenade launcher kit includes a rubber butt with a belt; return spring guide rod with latch (for installation on an automatic machine); bag for carrying a grenade launcher; two fabric bags in the form of fabric clips with nests of 5 shots each and a banner for cleaning and lubricating the barrel.

The grenade launcher is connected to the machine gun using a special bracket connected to the barrel by a press fit, while the bracket is held against longitudinal displacement by a pin. The grenade launcher is fixed in a certain position on the machine gun with a latch located on the bracket.

The trigger mechanism of the grenade launcher is of a self-cocking type, i.e., when the trigger is pressed, the trigger is sequentially cocked and decocked. The trigger mechanism has a blocking device, which makes it impossible to fire from a grenade launcher that is not attached or not completely attached to the machine gun, as well as when the shot is not completely fired into the barrel.

In addition, the grenade launcher is equipped with a safety catch, which prevents accidental shots after attaching the grenade launcher to the machine gun. The fuse box is located on the left side of the body and has two positions: “PR” (safety) and “OG” (fire). In the “PR” position, the safety locks the trigger.

The dynamic nature of the forces and stresses experienced by a machine gun when firing from a grenade launcher mounted on it is very significant. Therefore, when the grenade launcher reaches more than 400 rounds, the machine gun on which the GP-25 was installed is removed from service along with the grenade launcher, and in the future can be used further for its intended purpose, but without the grenade launcher, and the grenade launcher is inspected and checked for accuracy of combat by shooting at a test target. If satisfactory results are obtained, the grenade launcher can be used with another machine gun assigned to it.

The sighting device is an open type, mounted on the left wall of the bracket. On the same wall there is a distance scale. For direct fire at a visible target, a folding rear sight and front sight are used. In this case, grenades are fired along a flat trajectory from an automatic grenade launcher system at a distance of up to 200 meters with the butt resting on the shoulder (for this, the butt of the machine gun is equipped with an additional rubber butt pad, which softens the rather strong recoil). Aiming is carried out directly at the target or at a point in the target area. The sight is fixed using a ratchet-type mechanism. Corrections for side winds when firing from an under-barrel grenade launcher can be made by shifting the front sight.

The grenade launcher is loaded from the muzzle of the barrel. The tail part of the shot is inserted into the barrel of the grenade launcher and moves all the way into the breech.

For firing from a grenade launcher, 40-mm unitary VOG-25 rounds with a fragmentation grenade equipped with an instantaneous head fuse with a self-destructor were initially used. The VOG-25 shot consisted of a grenade with a fuse screwed into the head of the body and a propellant charge into the bottom. A fairing was mounted on the grenade body.

Automatic grenade launcher system, consisting of:
5.45 mm AK 74 M assault rifle, GP-25 under-barrel grenade launcher,
VOG-25 round, and a rubber butt pad

The bursting charge of a cylindrical explosive was intended to break the body into fragments and give them a certain dispersion speed. The explosive charge was pressed into the grenade body with gaskets. The cardboard mesh was intended to obtain an organized crushing of the body into fragments. The radius of continuous destruction by fragments when a grenade fell vertically reached 10 meters. The fairing mounted on the grenade body served to reduce the influence of air resistance.

The role of the cartridge case was played by a special chamber of a smaller caliber, located on the bottom of the grenade. Powder propellant charge designed to communicate with a grenade initial speed together with the igniter, it was located in the bottom part of the grenade body, which significantly simplified the loading of the grenade launcher and also increased its rate of fire. As soon as the grenade began to move, the VMG-K fuse began to be cocked. The fuse was cocked after the grenade flew out of the barrel at a distance of 10 to 40 meters from the muzzle of the barrel. When encountering an obstacle, a fuse was triggered, the detonating unit of which detonated the explosive charge placed in the grenade body. In case the fuse fails due to the reaction-inertial mechanism when encountering an obstacle or falling into water or viscous soil, the grenade had a self-liquidator that was triggered 14–19 seconds after the shot.

Stabilization of the grenade in flight by rotation made it possible to reduce the size and total weight ammunition (without reducing its power), which, in turn, contributed to an increase in portable ammunition. At the same time, the mass of the grenade and its size, which is quite large for small arms, combined with the low flight speed, made the shooting accuracy dependent on weather conditions, and primarily on the side wind.

In 1979, the ammunition load of the GP-25 grenade launcher was expanded with another 40-mm round - the VOG-25 P (“jumping”). It differed from its predecessor in the increased body length, a new VMG-P head fuse with an expelling charge in its front part and a pyrotechnic moderator, which ensured that the grenade “bounced” after it hit the ground and detonated in the air at a height of 0.75 meters when firing at all ranges of combat use of an under-barrel grenade launcher. A similar design solution of the new VOG-25 P ammunition made it possible to increase the effectiveness of the destructive fragmentation effect compared to the VOG-25: in terms of open enemy manpower - by 1.7 times, and in terms of enemy manpower hiding in trenches and trenches - by 2 times.

At the same time, for the use of GP-25 underbarrel grenade launchers in internal troops ah, the Ministry of Internal Affairs specially developed several more shots with grenades equipped with special equipment for this weapon. Thus, the set of ammunition for the GP-25 grenade launcher includes a “Nail” shot with a gas grenade filled with the irritating toxic substance Si 8. Subsequently, another “Nagar” shot, equipped with a smoke grenade, was adopted into service with the internal troops.

Ammunition of 10 shots is carried by the shooter in two fabric bags with sockets for shots, 5 in each. The bags are located on belts on both sides of the shooter's torso, so shots are available no matter what position the shooter is in. Unloading vests of types “A” and “B” can also have special pockets for shots for GP-25 under-barrel grenade launchers. During the battle, the machine gunner reports to the squad commander that half of his portable ammunition has been used up.

The machine gunner must always have three shots left for the grenade launcher as an emergency reserve, which is used only with the permission of the commander.

Weighing only 1.5 kg, the GP-25 Koster under-barrel grenade launchers significantly expanded the combat capabilities of the standard Kalashnikov assault rifle to destroy enemy personnel with shrapnel within a radius of 10 meters at ranges from 150 to 400 meters. The combat rate of fire of the GP-25 underbarrel grenade launcher reaches 4–5 rounds per minute.

The armament of two riflemen in a motorized rifle squad with under-barrel grenade launchers significantly influenced the expansion of the fire capabilities of Soviet infantrymen. The experience of combat operation of the GP-25 in Afghanistan revealed certain shortcomings in the design of the grenade launcher, including the ineffectiveness of firing at an invisible target due to the inability to adjust fire and the small portable ammunition load (10 shots). Among other disadvantages of the grenade launcher, it was noted that when the barrel becomes dusty, as well as when strong excitement It was quite difficult for the shooter to quickly load a shot, since it was necessary to get the leading protrusions of the belt of his grenade into the rifling of the barrel. Also, if the grenade misfired or was not fully loaded into the barrel due to its contamination, it was not always possible to quickly remove the grenade from the barrel.

Shooting rules

The GP-25 grenade launcher can be fired from any place from which a target or area of terrain where the enemy is expected to appear is visible. In this case, it is necessary to ensure that in the direction of shooting there are no closely located objects that interfere with the shooter, namely: tree branches, bushes, etc. This requirement must be strictly observed in order to avoid self-defeat of the shooter.

Firing from an under-barrel grenade launcher is carried out from the shoulder, from under the arm and with the butt of the machine gun resting on the ground, depending on the assigned combat mission and the characteristics of the firing position.

Shooting

To attach an assault rifle with an attached GP-25 underbarrel grenade launcher, in accordance with the service manual, the shooter is required, when firing from the shoulder, while holding the assault rifle with his left hand by the handle and without losing sight of the target, rest the butt of the assault rifle on his shoulder so as to feel a tight fit to the entire shoulder butt plate, index finger Place your left hand on the grenade launcher trigger.

The position of the elbows should be as follows:
- when shooting from prone and standing positions from a trench - placed on the ground in the most comfortable position;
- when shooting from a kneeling position, the elbow of the left hand is placed on the flesh of the left leg near the knee or slightly lowered from it, and the elbow of the right hand is raised to approximately shoulder height.

For firing from an under-barrel grenade launcher from under the arm, the position of the machine gun is the same as when firing from the shoulder, only the butt of the machine gun does not rest against the shoulder, but is pressed by the elbow of the right hand to the shooter’s torso.

The grenade launcher is fired by direct fire (flat and mounted trajectories) and semi-direct fire (mounted trajectory). When firing directly, aiming is carried out directly at the target or at a point in the target area; when firing with semi-direct fire, the grenade launcher is aimed at the target in the direction of the target, and the required elevation angle is given to the grenade launcher's barrel along a plumb line.

Depending on the combat situation (the mission received, the nature of the target, the distance to it, the nature of the terrain), the machine gunner can fire from an under-barrel grenade launcher from various positions:
- at a distance of 100 m - lying down and lying down;
- at a distance of 100–150 m - from the knee from the shoulder and standing from the shoulder;
- at a distance of 200–400 m - from the knee from under the arm, sitting from under the arm and standing from under the arm;
- for semi-direct fire - from the knee or while sitting with the butt of the machine gun resting on the ground.

While on the move, fire from an under-barrel grenade launcher is fired from a short stop.

If necessary, a grenade launcher can be fired from an armored personnel carrier (BMP) from a standstill, from a short stop through the landing hatches; to fire, the machine gunner takes a comfortable position, observing safety measures.

When preparing a firing position in advance, it is necessary to check the possibility of firing in a given sector or direction from both a GP-25 grenade launcher and an assault rifle, for which the grenade launcher and assault rifle are sequentially aimed at various points in the terrain where the enemy may appear. For ease of firing, it is necessary to prepare a support for the barrel of the grenade launcher. To soften the hard stop, cover it with turf, a rolled-up raincoat, a roll of an overcoat, etc.

GP-25 underbarrel grenade launcher kit:
1. GP-25 underbarrel grenade launcher
2. Bag for carrying the grenade launcher
3. Cleaning rod
4. Bannik
5. Rubber butt pad for machine gun butt
6. Base of the return mechanism of the machine
7. Bag for carrying shots

To select a sight and aiming point when shooting direct fire, it is necessary to determine the range to the target and take into account external conditions, which can affect the range and direction of the grenade. The sight and aiming point are selected so that the average trajectory passes through the middle of the target. The sight, as a rule, is set according to the distance to the target, the aiming point in normal (close to the table) conditions is usually chosen in the middle of the base of the visible part of the target, and if the shooting conditions significantly deviate from the normal (table) the point is chosen in the target area, distant from the middle its lower edge by the amount of the lateral correction, if the correction is known to the shooter.

When shooting with semi-direct fire, the sight is set, as when shooting with direct fire, according to the range to the target, but the second half of the sight's distance scale is used, and the aiming point is not designated. Horizontal aiming of the grenade launcher is carried out at any point in the terrain located in the target range, and vertical aiming is carried out along the plumb line of the sight. At the same time, the maximum sighting range The firing range is 400 meters, and the minimum target range for indirect fire (with an overhead trajectory) is 200 meters.

When firing along a mounted trajectory with elevation angles of up to 80 degrees (from closed positions at unobserved targets) at ranges from 100 to 400 meters, fire is carried out using a remote scale for remote shooting (at barrel elevation angles of more than 45 degrees) and a plumb line suspended on sight axis; with the butt clamped under the shooter's arm or with the butt of the machine gun resting on the ground. In this case, the grenade launcher acts as a mortar.

Moreover, to fire at minimum ranges (100 meters), a crane device was initially used in the design of the grenade launcher. However, military tests revealed that this device was irrational, so in subsequent series it was removed, and the minimum range for mounted firing was increased to 200 meters.

When shooting in conditions significantly different from normal (significant deviations in air temperature, strong wind, rain, snowfall, etc.), the aiming point may not be indicated; in this case, the machine gunner selects it independently.

At observed targets, it is more advisable to fire directly (flat and mounted trajectories). When the target is not visible (located in a trench, trench, on the reverse slopes of heights), but the distance to it and direction are known, fire at semi-direct fire (overhead trajectory).

When firing direct fire, the sight is usually set in accordance with the range to the target: the aiming point in normal (close to the table) conditions is usually chosen in the middle of the base of the visible part of the target, and if the shooting conditions significantly deviate from the normal (table) conditions, the aiming point is chosen in the target area, spaced from the middle of its lower edge by the amount of the lateral correction, if the correction is known to the shooter.

Sighting device for the GP-25 underbarrel grenade launcher,
installed for direct fire
(hinged trajectory)

A headwind reduces, and a tailwind increases, the grenade's flight range. The side wind deflects the grenade in the direction the wind is blowing.

Correction for deviation of firing conditions from normal when preparing initial data for firing from a grenade launcher is usually taken into account by moving the aiming point out based on the results of previous firing in similar conditions.

Fire adjustment is made: in direction - by moving the aiming point out in height; in range, if the deviation of the grenade explosion from the target is more than 50 meters - by changing the sight setting.

The aiming point is set to the amount of deviation of the grenade explosion from the target in the direction opposite to the deviation.

If the grenade explosion deviates from the target at a distance of less than 50 meters, then correction can be made by changing the height of the front sight relative to the rear sight, for example, when shooting at 200 m, changing the front sight to its entire height changes the grenade’s flight range by about 14–16 m.

At night, firing from a grenade launcher is carried out only by direct fire (flat and mounted trajectories) at illuminated targets. Shooting is carried out in the same way as during the day.

Loading the GP-25 underbarrel grenade launcher

To load a grenade launcher you need:
- take right hand the machine gun by the receiver between the magazine and the handle of the grenade launcher, holding the machine gun in the direction of the target (when loading the grenade launcher in the prone firing position, it is allowed to rest the machine gun with the magazine on the ground), remove the shot from the bag with your left hand; for ease of preparation for shooting, for the first loading, use the first shot from above in the right row;
- insert the shot with the tail into the barrel of the grenade launcher and push it until it stops in the breech and the latch sinks into the shot’s locking groove, and a click of the latch should be heard. In this case, the spring-loaded latch, which is also a fuse that prevents firing when the VOG-25 is not fully loaded, slides into the locking groove and holds it in the barrel bore (when the latch sinks into the locking groove, a characteristic click will be heard on the shot). If the shot does not advance into the barrel, then it is necessary, simultaneously with the advance, to rotate the shot around its axis until the protrusions of the shot align with the rifling of the barrel - after loading, take the machine gun to the appropriate position for firing;
- if shooting is not carried out immediately, you need to put the translator in the “PR” position.

Discharging GP-25

To unload the GP-25 grenade launcher, it is necessary to check that the translator is set to the “PR” position; take the machine gun with your right hand by the receiver between the magazine and the grenade launcher handle and give the barrel a slight elevation angle; With your left hand, take the grenade launcher from below by the body of the trigger mechanism, and with the thumb of your left hand, push the extractor forward; grab the muzzle of the grenade launcher barrel with your left hand, give the barrel a declination angle with your right hand, and then remove the shot from the barrel with your left hand and put it in the bag.

Security measures

When handling the GP-25 grenade launcher, the following safety precautions must be strictly observed:
- in all cases when the grenade launcher is not firing, the grenade launcher must be on the safety catch (translator in the “PR” position), remove the grenade launcher from the safety lock only before firing;
- you cannot use faulty grenade launchers;
- when preparing a grenade launcher for firing, it is necessary to protect the barrel from water, sand, dirt and other foreign objects getting into it;
- you cannot load a grenade launcher if there are foreign objects in the barrel;
- you cannot perform any work with a loaded grenade launcher that is not related to firing a shot;
- before eliminating delays that occurred during firing, first unload the grenade launcher;
- unload the grenade launcher only after putting the grenade launcher on safety;
- when unloading, direct the barrel of the grenade launcher towards the targets (targets).

It is strictly prohibited:
- firing from a grenade launcher, if the recoil spring guide rod with a latch and the butt plate with a belt, which are included in the grenade launcher kit, are not installed on the machine gun;
- firing from a grenade launcher at elevation angles of more than 80 degrees;
- firing from a grenade launcher with the butt of the AKMS and AKS 74 assault rifles folded;
- firing from a grenade launcher with a bayonet attached to the machine gun (for AK 74 and AKS 74 machine guns).

In case of misfire, you must press the trigger again; if it misfires again, wait 1 minute, remove the shot from the barrel and inspect it; If any damage to the primer is detected, do not use the shot for firing. Such shots must be destroyed.

Combat properties, general device, purpose of main parts and mechanisms, procedure for partial disassembly. The design of the shots used.

Purpose

The GP-25 underbarrel grenade launcher is an individual weapon and is designed to destroy open manpower, as well as manpower located in open trenches, trenches and on reverse slopes. The grenade launcher is used in conjunction with a Kalashnikov assault rifle.

Combat properties:

caliber, mm - 40
number of grooves - 12
sighting range, m:
maximum – 400
min. with hanging trajectory - 200
effective firing range, m
fragmentation grenades - up to 250
irritant grenade - up to 200
combat rate of fire, r/min. - 4-5
weight of the grenade launcher without butt plate, kg - 1.5
portable ammunition, rds. - 10
initial grenade flight speed, m/sec - 76
fuse arming range, m - 10-40
grenade self-destruction time, sec - not less than 14
rupture height (on medium-hard soil) VOG-25p, m - 0.75
shot weight VOG-25, VOG-25p, kg - 0.225
weight of the "Nail" shot, kg - 0.170
Type of shots used:
VOG-25 (with fragmentation grenade)
VOG-25p (with bouncing fragmentation grenade)
VOG-25in (shot in inert ammunition)
“Nail” (shot with an irritant gas grenade)
Expansion radius lethal fragments, m - up to 7

General device

The GP-25 is mounted under the barrel of the machine gun. It consists of 3 main parts:

barrel with sighting device and bracket for attaching to a machine gun
breech
trigger housing with handle

The grenade launcher kit includes:

butt plate with belt
return spring guide rod with latch
grenade launcher bag
shot bag
banner
cleaning rod (cleaning device)

With the GP-25 attached, the machine gunner, depending on the task at hand, can fire from both a grenade launcher and a machine gun.
Firing is carried out by direct and indirect fire (flat and mounted trajectory).
To alleviate the recoil force, which when firing from a grenade launcher is slightly greater than when firing from a machine gun, a special rubber butt pad is installed on the butt of the machine gun.

Purpose of the main parts and mechanisms of the grenade launcher

Trunk The grenade launcher serves to direct the flight of the grenade, has 12 rifling, curling from left to top to right, serving to give the grenade a rotational movement during flight, which ensures its stability along the trajectory.

bracket designed for attaching a grenade launcher to a machine gun and placing sighting devices. The front and rear supports of the bracket have seats for mounting a grenade launcher on a machine gun.

Aim serves to aim the weapon at the target when firing from a grenade launcher.

There is a distance scale on the bracket on the left under the sight.
Distance scale: first group of numbers ( white) from 1 to 4 is intended for installing sights when shooting direct fire (flat trajectory). Intermediate divisions correspond to firing ranges of 150, 250 and 350 m.
The second group of numbers (red) is intended for semi-direct fire (overhead trajectory).
At direct fire(for shooting with a flat or mounted trajectory), aiming is carried out using one guide aiming line passing through the middle of the rear sight slot, the top of the front sight to the aiming point.
With semi-direct aiming(for shooting with a mounted trajectory) aiming is carried out separately:
- in the horizontal plane, guidance is carried out on the front sight so that it is on target
- in a vertical plane along a plumb line - the machine is given such an angle that the mark on the plumb line coincides with the mark (11) on the stopper sleeve

The plumb line serves to give the grenade launcher the necessary elevation angles when firing with indirect fire (overhead trajectory) at unobserved targets located on reverse slopes, terrain folds or in open trenches and trenches. It is installed on the sight axis using a plumb bob bushing and a stopper bushing.
The sight spring presses the plumb bob bushing against the closing protrusions of the sight axis and thus secures the sight in assembled form.
The sight stopper ensures that the sight cannot be reset at the moment of firing; the stopper spring holds it in the upper position.

Breech: is a camera high pressure, in which the grenade propellant charge burns.

Trigger housing with handle connects to the breech and together with it represents a part of the grenade launcher, separated from the barrel with a bracket when the grenade launcher is placed in a carrying bag. The housing houses the trigger mechanism.

Lever serves to hold the grenade launcher when firing; it is connected to the body by means of an elastic lock.

Frame The housing covers the forend of the machine gun and protects it from mechanical damage when firing. An elastic insert is glued into the body frame, which serves to prevent hard impacts on the receiver of the machine gun when firing from a grenade launcher.

Shock trigger mechanism serves to fire a shot from a grenade launcher.
It consists of:

trigger with striker
release with spring and rod
pusher
mainspring
oppression

Translator when set to the “PR” position (the lever is in a vertical position), it locks the trigger, protecting the loaded grenade launcher from an accidental shot. Before firing a shot, the translator should set the lever in a horizontal position to the “OG” position), thereby releasing the trigger.

Butt pad serves to soften the recoil force when firing from a grenade launcher when the butt of the machine gun is resting on the shoulder of the shooter and to prevent deformation of the butt of the machine gun when firing with the butt resting on hard ground.

The procedure for partial disassembly and assembly of a grenade launcher

Disassembly of a grenade launcher can be incomplete or complete.
Partial disassembly is performed during routine maintenance.
Complete disassembly is carried out during maintenance, for cleaning in case of severe contamination, after the grenade launcher has been exposed to rain or snow, and during repairs.

The grenade launcher is disassembled and assembled on a table or clean mat (tarpaulin). Place parts and mechanisms in the order of disassembly, handle them carefully, do not place one part on top of another, do not allow impacts hard objects and against each other, do not use excessive force when disassembling and assembling.
The procedure for incomplete disassembly of a grenade launcher:

Reassembly after partial disassembly is carried out in the reverse order:

attach the breech to the trigger body
insert the housing axis and translator into their holes
attach a check
attach the barrel to the trigger body
put the translator in the "PR" position

Shot device VOG-25, VOG-25P and “Nail”

VOG-25 fragmentation rounds and VOG-25p fragmentation and bouncing rounds are designed to destroy enemy personnel and fire crews with fragments.

A shot with a “Nail” grenade is designed to create a gas cloud with an intolerable and permissible concentration of an irritating substance; it is used both in a combat situation and during special operations.

Shot VOG-25

Shot VOG-25P

Unlike the VOG-25 shot, the VOG-25P shot device has an ejector powder charge(3), which, when a grenade meets an obstacle (the ground), breaks off the connecting thread (12) by the force of the resulting pressure, pushes the fragmentation jacket of the grenade with an explosive charge to a height of up to 1.5 m, where it detonates, due to this the efficiency is significantly increased hitting the enemy with shrapnel.