According to known data, the development of a special light mortar, which has special combat capabilities, began in the middle of the last decade. The development of this product was engaged in the Central Research Institute "Petrel", which has extensive experience in creating a variety of artillery systems. The first phase of development work was completed by 2008, when the project data was first published. A few years later, the public was shown a finished mortar and a shot for it.

The first version of the mortar "Supermodel". Photo Russianarms.ru
The development of new weapons was carried out in the framework of experimental design work with the funny name "Supermodel". Subsequently, the finished mortar received a more serious name - "Gall". According to the index system of the Main Rocket and Artillery Directorate, it was designated as 2B25. New development has received wide popularity under the last two designations.
The product 2B25 is intended for the defeat of manpower or other unprotected targets on the battlefield or in undisclosed shelters. From the point of view of combat use, in general, the same requirements were imposed on him as to other mortars. At the same time, in the technical task there were special items. First of all, it was necessary to reduce the size and weight of the weapon to simplify its transportation. In addition, it was necessary to eliminate the flash shot and reduce its noise to the lowest possible values.
The task of facilitating transportation was solved in an obvious way. In the construction of the mortar used components and aggregates of reduced dimensions and, accordingly, reduced weight. A number of parts were made of light alloys, which allowed to maintain acceptable strength. The second goal of the project was achieved by developing a completely new ammunition and a certain change in the design of the barrel. In fact, "Gall" combined in itself the construction of the barrel mortar and the principle of the action of the hatch. However, he could only use certain mines.
It should be noted that there are two known variants of “Galla”, which have certain differences. So, the very first version of this weapon, the existence of which became known at the end of the last decade, was distinguished by a relatively long barrel and a simplified base plate design. In the future, the length of the trunk was reduced, and with it was proposed to use another reinforced plate. Some other devices of the complex were also reworked.
Mortar 2B25 is not very complex design and, in general, is based on standard solutions for such weapons. Structurally, it is divided into the barrel, bipedal-carriage, support plate and sight. The possibility of partial disassembly of the mortar for laying in the shipping box. Also carried the carrying of mortars and ammunition for him with belts and bags or backpacks of appropriate dimensions.
The largest element of the mortar "Gall" is a smooth barrel caliber 82 mm. It has a length of about 600 mm and is the main part of the weapon, with which all other units are connected. The barrel is made in the form of a pipe with an open front end. The breech of this part is covered with tiles, on which is placed the casing of the firing mechanism. The shank of the latter has attachments for connection with the base plate. In connection with the use of a special ammunition, the barrel does not experience heavy loads, and this made it possible to make it as thin and light as possible.
Inside the barrel is a longitudinal guide rod that performs several functions. First of all, it is used as a guide for putting mines on the desired trajectory and in this regard undertakes part of the barrel’s tasks. In addition, it performs the functions of a firing pin of the firing mechanism responsible for the ignition of the propellant charge. The drummer is controlled by a lever bred outside the casing of the mechanism.
Close to the muzzle of the barrel clamp is fixed, which is bipedal. With its help, a system of the so-called type is formed. imaginary triangle. The protrusion of the barrel clamp is connected to a helical horizontal guidance mechanism, which allows the barrel to be deflected 4 ° to the right and left from the neutral position. The U-shaped support of the horizontal guidance mechanism is connected to a vertical guidance device. The permissible vertical alignment angles are from + 45 ° to + 85 °. The mechanism of vertical guidance is fixed between the adjustable bipod. Bipedal can fold for transportation. In this case, the supports are brought together, and the whole product is laid along the trunk.

Mortar at the shooting range. Photo Bastion-karpenko.ru
On the back of the casing of the firing mechanism there is a ball bearing for connection with the slab, which transmits recoil to the ground. In this case, the plate actually consists of two parts. The first of them is a disk with several holes, in the center of which is placed the glass for the ball, equipped with a clamping screw. The second part is the base plate itself. It was made in the form of a larger disc with a large central hole, above which there is a low cylinder. These two planes are connected by triangular struts. The disc mounted on the barrel is proposed to be placed inside the base plate. The slab, depending on the characteristics of the soil, can be installed one side or the other down, ensuring efficient transfer of the load.
Next to the collar to install the bipods on the trunk is a similar mount for the sight. In the basic configuration, the Gall is equipped with an MPM-44M optical sight, designed for firing from closed positions. The sight has a couple of levels for leveling and one for vertical guidance. Scales for coarse and precise targeting are also provided. Scales and reticle are equipped with lights for shooting in the dark.
With the 2B25 mortar it is proposed to use special silent fragmentation mines of the 3BO35E type. During their creation special engineering solutions were used, which made it possible to ensure the fighting qualities at the level of existing 82-mm mortar shells, but at the same time sharply reduce the volume of the shot.
A new mine received the head of a characteristic form, containing an explosive charge and spherical ready-made attack elements. In the protruding front of this device is placed a pin fuse. According to the developer, the warhead of the 3BO35E mine with its own mass of 1,9 kg forms a field of fragments with damage parameters no worse than the serial 82-mm min. At the same time, the promising product differs from the serial size of the warhead and body parameters.
The new type of mine has a long tubular shank, on the back end of which a stabilizer with a large number of feathers is placed. Inside the shank there is a tubular channel of the required diameter. The propellant charge is placed in front of the shank, and behind it in the channel is a special piston. In the shank of the 3BO35E mine, the principle of shot noise reduction is implemented due to the so-called. locking powder gases. When fired, the piston provides acceleration of the mines, but then stops and does not allow gases to escape from the shank.
Mortar 2B25 and its ammunition are small in size and weight. The weapon itself in combat position weighs only 13 kg, and also occupies a minimal place. The silent mine has a total length of 60 cm. The mass of the product is 3,3 kg, of which 1,9 kg falls on the warhead with an explosive charge and ready-made fragments.
The limited propellant charge inside the mine allows you to fire on the mounted trajectories at a distance from 100 to 1200 m. The design of the weapon provides shooting in any direction - when you rearrange the two-legs. Without moving it, shooting is possible only in a sector of width 8 °. The maximum rate of “Galla” reaches 15 rounds per minute, but the need to restore the pickup can drastically reduce this parameter.
The development organization proposes to transport the 2B25 mortar and 3BO35E mines using standard capping boxes. The scope and base plate are removed from the mortar before transportation, while the bipod is folded along the barrel. Further, all components of the weapon fit into the box. Mines are initially shipped in wooden boxes with retainer cradles.
In the field, a mortar can be transported using a simple carrying strap: the barrel has an sling for attaching it. It is also possible to place the mortar in backpacks of appropriate sizes. For carrying several minutes it is suggested to use a large textile pouch. Thus, the calculation of a two-person mortar can, with acceptable convenience, carry both the weapon itself and sufficient ammunition for it.
The principle of operation of the silent mortar is quite simple. For a shot, it is proposed to place a mine in the barrel, putting its shank on the longitudinal rod. Pressing the trigger lever moves the hammer and ignites the propellant charge inside the mine. Powder gases, expanding, cause the piston to move along the channel of the shank and put pressure on the rod. Due to this, the mines are being dispersed - as in barreled mortars. The difference from the traditional scheme with a rod is the presence of a moving piston, which is blocked at the rear of the shank and does not allow gases to go outside, creating a flash, a shock wave and noise.

The breech and base plate of the split layout. Well visible stock inside the barrel. Photo Russianarms.ru
However, such a design of weapons and ammunition does not exclude the formation of some sounds. The details of the firing mechanism emit a clank, and a similar sound is accompanied by the movement of a mine along the guide rod. At the same time, the Gall mortar is much quieter than other 82-mm systems. By loudness, a shot with a special mine is compared to firing from a machine gun with a noiseless firing device.
Another characteristic advantage of the “Galla” over other mortars of its caliber are reduced dimensions and weight, which simplify transportation. However, such advantages have to be paid for by reducing the firing range.
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The first information about the existence of a promising silent mortar appeared at the end of the last decade. In 2011, the Petrel Research Institute for the first time showed a new development at one of the international exhibitions of weapons and equipment. Subsequently, 2B25 "Gall" repeatedly became an exhibition exhibit and always attracted the attention of specialists. Shortly thereafter, the experimental products were sent for tests in the interests of the Russian military department.
A few years ago, the development organization spoke about its plans for further improving the existing design. To improve the combat and operational characteristics, it was planned to develop a new version of the base plate, new means of carrying, etc. At the same time, as far as is known, the refinement of the munition and the principles of its work were not planned. There were also no intentions to create new mines with a different warhead.

Carrying and container for mortar and its ammunition. Photo TsNII "Petrel" / burevestnik.com
According to reports from past years, the Gall mortar may be of interest to domestic special forces, in service of which there must be a special weapon with characteristic capabilities. However, until a certain time information about the procurement of these products was missing. New information about the promising mortar appeared relatively recently - in August, according to the results of the military-technical forum "Army-2018".
Jane's publication, citing an unnamed source from the exhibition, reported that the Russian Ministry of Defense intends to purchase various mortars of a number of models. Among other things, the delivery of several dozen 2B25 products is scheduled. Such mortars are intended for special operations forces. The exact number of mortars and mines planned for the procurement, the timing of contracts, etc. not yet reported.
A few years ago, "Gall" was offered to foreign buyers. According to Rosoboronexport, several foreign armies have already become interested in a silent mortar, and in the near future contracts for the supply of such weapons may appear. However, it is not specified yet who exactly can become new customers.
There is reason to believe that the 2B25 mortar can show very good results on the international market. It is designed to solve special problems and belongs to a specific class of weapon, which has not yet become widely spread. Thus, in the struggle even for small contracts, “Gall” will not have to deal with many competitors, which will simplify the receipt of orders.
To solve special problems, special weapons with unusual capabilities may be needed. The promising Russian mortar 2B25 "Gall" is capable of firing a target even from minimal distances, without unmasking itself with noise and a flash of a shot. According to the latest data, in the near future, such weapons can enter Russian special forces. Together with unusual mortars, special forces will receive new opportunities and advantages over the likely adversary.
On the materials of the sites:
http://burevestnik.com/
http://russianarms.ru/
https://defendingrussia.ru/
http://arms-expo.ru/
http://janes.com/
https://ria.ru/
http://tass.ru/