
As you know, almost any military conflict is the debut of handicraftsmen who repeat over and over again, bringing new models of field modifications of military equipment to the mountain in order to eliminate its shortcomings or expand combat capabilities. True, it doesn't always work out well. However, what is there cannot be taken away.
The special military operation in Ukraine was no exception in this regard: all sorts of “modernizations” appear both from the Ukrainian side and from our side, which we have repeatedly written about and even shown. But in this case, it seems that handicraft creativity was trampled down and trampled down already by factory manufacturers, who rather shocked the public with their work in the face of MT-LB with 2M-3 ship installations equipped with twin 25-mm automatic guns.
Originally from Vladivostok
Still, as has already been said, handicrafts are already familiar in a special military operation so much that each new product of its activity is perceived as something ordinary. Well, once again, a “visor” was welded onto the tank, dynamic protection units were hung over any measure, or a truck was surrounded in a circle with steel sheets. As they say, in an effort to protect yourself to the maximum, no impulses are alien. Yes, and those same long-suffering "motorcycle leagues" that MT-LB are regularly modified with various machine-gun and cannon mounts.

But the “motorcycle league” with the 2M-3 ship bandura, armed with two 25-mm cannons, at first even seemed like some kind of fake, or at least a one-time action from radical field designers. However, for the first time, the same point of view was also held in many military communities in social networks and forums. But no, the monster turned out to be still serial, albeit with the prefix "fine", and by no means handicraft.
As it turned out, the vehicles were equipped with ship installations in Vladivostok, and specifically for the 155th Separate Pacific Marine Brigade. fleet, whose units are currently participating in the battles in the Donbass.
2M-3 in naval reserves, including those of the Pacific Ocean, has accumulated since deep Soviet times, if not in excess, then clearly in sufficient quantities - since the fifties of the last century, many projects of combat and auxiliary ships have been equipped with installations, and even on Today, they have not lost their relevance yet. And given that shells for them are also literally in bulk, the rationalization proposal for equipping them with tracked vehicles seemed interesting to someone from the command.

It is difficult to judge what this very interest was based on: something suggests that the reason was not the combat experience gained during the special military operation in Ukraine, but the banal need for specialized fire weapons. But, as they say, we have what we have.
Moreover, although the 2M-3 is originally a ship-based means of self-defense against surface and air targets at a slant range of up to three kilometers, the very fact of its transplantation to land vehicles is not limited to the current "motorcycle leagues".

Gun mount on an armored train
Thus, there is evidence that similar ersatz on MT-LB were used by the soldiers of the Azerbaijani army during the conflict in Nagorno-Karabakh, as well as the military armies of President Bashar al-Assad in the civil war in Syria.
Also, 2M-3 in the 60-70s for the purpose of air defense were installed on Soviet armored trains in the regions of the USSR bordering China. And in the GDR, IFA W50 trucks were equipped with this small-caliber artillery system - again, with the intention of creating a mobile anti-aircraft gun.

2M-3 on the chassis of the IFA W50 truck
What is 2M-3?
The appearance of this small-caliber gun mount does not need a special description: in fact, it consists of a fixed barbette - a cylindrical steel "glass" - on which there is a rotating open tower of complex geometric shape with an inclined arrangement of armor plates in the frontal part.

Armor, by the way, cannot boast of a particularly large thickness - only up to four millimeters, so even the status of exclusively anti-fragmentation for it in modern conditions is a stretch. Such a serious drawback was dictated not only by the design features and requirements of the project, but also by the desire of the designers to make the 2M-3 a universal contraption with a relatively small mass, which could be installed even on a civilian ship.
All that it can withstand: small-caliber ammunition fragments and light rifle bullets weapons, and that's not all. But it weighs one and a half tons, which, taking into account its layout and equipment, is not so much, and the carrier itself in the person of MT-LB is not much better protected.
Inside the movable turret there is a twin artillery system in the form of two 25-mm belt-fed 110-PM automatic cannons (box-shaped round magazines for 65 rounds), created on the basis of the 84-KM anti-aircraft gun from the Great Patriotic War and providing a rate of fire in the range of 270–300 shots per minute per barrel. Their ammunition load includes two main types of shots: with armor-piercing tracers and fragmentation-incendiary tracers with an initial flight speed of about 900 meters per second.
The barrels are air-cooled, but during the reloading process, it is possible to run water through them. However, this is hardly guaranteed on MT-LB.

To the left of the machine guns is the gunner's place. Of the sighting devices at his disposal there is only a KMT-25 annular foreshortening sight and nothing more. Yes, yes, the same antediluvian - by today's standards - round sight, which, in spite of everything, does not lose its relevance.
To aim the gun mount at the target, the gunner has, as it is now fashionable to call it, a kind of joystick. If you turn it to the right or to the left, the tower will start moving in the corresponding direction. Up or down - guns will move vertically. However, there are no buttons for making shots on it, unfortunately. This is done with a pedal under the gunner's foot.

View of the 2M-3 gun mount from the stern. On the left, at the gunner's place, you can observe an annular sight.
The actuators of the hydraulic system located in the turret and turret barbette are responsible for providing these maneuvers with fire, with the help of which the horizontal rotation of the installation is carried out at a constant speed of 40 degrees per second, the vertical guidance of the guns in the range from -10 to +85 degrees, as well as the final stage of their reloading - cocking. Although, in the event of a hydraulic failure, completely manual guidance is also possible, which, of course, affects the effectiveness of the fire in the most unpleasant way.
Some nuances
Still, the fleet for 2M-3 is a native element, therefore, when it comes to transferring it to the MT-LB chassis, a number of questions arise that require at least some kind of solution, because otherwise this whole monster will even be more or less tolerable "gantrak" does not pull, from the word at all.
First of all, we are talking about, to put it mildly, not a very good weight balance: the published footage clearly shows that the stern of the MT-LB, where the gun system is installed, sank in order. It is understandable - 2M-3 weighs one and a half tons, so the suspension of the "motorcycle" from such a load, in any case, will not say thanks to the creators of this ersatz.

At the same time, there are no details yet regarding the foundation for the 2M-3 - I really want to hope that the barbette has somehow been extended in length to the bottom of the "motorbike", otherwise the center of gravity is at a dangerous height. This threatens with the fact that the car can tritely collapse on its side or back itself when overcoming even not the steepest bumps, and, unfortunately, there are enough of them on the fronts of the special operation.
Also noteworthy is the electrical part.
There is some feeling that the hydraulics of the 2M-3 were abandoned and switched to fully manual guidance, since this is the simplest solution that does not require labor, but predictably affects the effectiveness of firing. Simply because in the case of retaining hydraulic drives, it would be necessary to tinker with the power supply of the electric motor of the hydraulic system pump.
The MT-LB generator produces a voltage of up to 30 volts with a power of up to about 3,7 kilowatts, and the ship’s installation can “eat” the outlet voltage that is quite regular for us and consumes power from the on-board network of 0,95 kilowatts. The only question is converters and other electrical equipment that can start the hydraulics of an art installation. That is, the task is quite solvable, but have they taken up this?
I would also like to say a few words about loading automatic guns, but it doesn’t make much sense: magazines weighing half a centner are inconvenient to carry both through the roof of the 2M-3 tower, and from under the barbette, if such a possibility was provided. And so and so - it's very difficult. In combat conditions, in a moving car, and even in a limited space, to operate with such weights ... The occupation is not very attractive.
How will they apply?
Unfortunately, the armed forces, and we are talking not only about Russian, but also foreign, the structure as a whole is very inflexible, therefore, each type of military equipment is assigned its own strictly defined tasks, although sometimes this stereotype successfully fades into the background on the ground.
Nevertheless tank other tasks, except for tank ones, are not yet attributed. As well as infantry fighting vehicles and armored personnel carriers. However, where this Pacific monster on a tracked chassis will join is not yet very clear, simply because it should not be. This is not a regular unit, but a first-class ersatz.
On various sites and forums, this MT-LB with a ship-mounted gun mount has already been credited with the capabilities of an almost cheap alternative to the Terminator BMPT, especially mentioning its huge gun depression angles - they say, 85 degrees will allow you to reach all floors in the city, and fire in the field from two 25-mm trunks, it will crumble everything that is possible.
And there are no questions about the artillery part: a twin of two 25-mm machine guns really provides a monstrous density of fire for ground vehicles, and the aiming angles seem to be good. Just what to do with a turret installation open from above, absolutely no armor and dubious cross-country ability? And this is without taking into account the process of reloading guns on a tracked chassis, which is too problematic to describe without a mat.
Still, as a mobile fire system capable of covering the enemy with a hail of fragmentation shells from a relatively long distance (within a direct shot), the MT-LB with 2M-3 looks preferable. And we already have experience of this: "motorcycle leagues" with the ZU-23-2 have been performing this function for a long time, but the shooter is practically not protected in any way, and here the rotating tower is also available. It remains to be hoped that this contraption will not be tried on for the role of an infantry fighting vehicle or an armored personnel carrier.
Well, as a free judgment, you can see that the 2M-3 is primarily an anti-aircraft gun. Without external support, of course, she will not be able to fully express herself, since from the observation systems she has at her disposal only the eyes of the gunner himself. However, in the presence of external target designation, at least in azimuth, which can be provided by both radar and infrared means of detecting air targets, its effectiveness increases many times over. Which, in fact, is ensured in the organized air defense system of a warship.
Even the presence of some Strela-10 can make a conventional MT-LB battery with 2M-3 a more or less tolerable barrage armada, capable - in conditions of acceptable visibility - to fight at least low-speed and low-altitude drones-kamikaze, but so far it is written with a pitchfork on the water.