So it was that type of firearm that was created for the implementation of the water, it was created a little. Moreover, not all of them were able to reach mass production. The main problem, which had to fight weapons designer, was the density of water. Do joke, almost 800 times denser than air and leads the interaction with the bullet accordingly. The resistance of the water just does not give bullets ammunition available to accelerate to more or less respectable speeds and fly (or float), or even slightly applicable distance. So frogmen had to enjoy what is — in the air to use the "normal" tool, and under the water to get knives.
But in 1971 adopted Russian special forces entered SPP-1M pistol cartridge and the PCA. Their main feature, which is, in fact, permitted to obtain the required properties of fire — a bullet. For more than a measured behavior in the water and it made a longish like a nail.
The smallness later, in the middle of the 70s, Klimovskii TsNIITochmash developed its own version of the "needle" chuck. The designer Simonov on the basis of standard chuck sleeve 5.45 × 39 mm cartridge made MEAs. As with PCA, the bullet cartridge Klimovsky had a length of about 120 mm. Also relevant feature of the bullet is a blunted head part — the motion in the water it makes the cavitation chamber, which dramatically lowers the resistance of the water. This method has solved the problem at the same time stabilize the bullet while moving in the water. After a series of investigations, it was decided to change the caliber of the bullets from 5.45 to 5.66 mm. More precisely, it was not necessary to change anything. Submachine gun set up for cartridge MPS had to be smooth, but a real bullet caliber 5.45 x 39 mm cartridge is equal to exactly 5.66 millimeters. It is also possible to do a better job of sealing the joints "bullet-liner." The smallness of the later was made patron MPST different from the original presence of the tracer.
Immediately with a cartridge in the development of the IPU was a special underwater machine (ABS). This machine was built on the basis of the vapor circuit. Locking in the MTA is turning the bolt. At first glance, nothing extraordinary, but the designers under the direction of Simon had to reflect on by some parts. In 1-x, on the supply cartridge has a longish. 2nd question: providing health MTA and under water, and air. First decide the problem of using store-specific shape (see photo) for 26 rounds and a longish shutter speed. Because of this, the fuse-translator fire had to be placed not on the right side of the receiver, like a Kalashnikov assault rifle, and on the left. To be able to function implements a 2-media designers have introduced a system of automatic vapor-gas regulator. When shooting in the air he throws a part of powder gases. In water, respectively bullet accelerates total gases. Gazoregulyator handy for the reason that for underwater shooting pool more energy is required for the flight of the barrel — to push the bullet out of the water last. The trigger has a back-and-mainspring and allows you to do both single shots and turns. All the mechanics machine adapted to work in the "viscous" aquatic environment.
Sights APS simplest outdoor fixed rear sight on the receiver and the front sight on the gas outlet tube. APS also has a retractable buttstock. Curiously, in the absolutely retracted frame shoulder rest on one hundred percent lies in the special notches on the handle of fire control. The trigger guard and hook were made regarding bolshennymi, that soldier could shoot without removing the gloves.
That still gave all those bullets, nails, etc. gazoregulyatory? Under water at a depth of about 5 meters, effective range of fire is 30 meters deep, 20 meters away, you can shoot is only 20. With all of this in both cases the energy of the "nail" enough to break through the suit with a foam lining or points of Plexiglas (5-7 mm), and the next defeat the opponent's body. Curiously, underwater visibility is usually not greater firing range APS. In air, the bullet killing power remains at a distance of 100 meters. But the bullet, unadapted to air, at such distances gives simply indecent deviation. So the real battle for the MTA range in air is not very different from that seen in the water, that for most of the shootings are not many. Another reason against the use of APS is not in the water — a resource. Machine capable to shoot under water 2,000 times the air is able to do only 180 shots — a tribute to optimize work under water.
Almost immediately APS was adopted. Create settled on the Tula arms factory, and it is small batches. Now officially machine is in service only in Russia. Zabugornye countries have the opportunity to order the MTA through Rosoboronexport, but so far they only expressed their purchasing ability.
Despite its uniqueness, the MTA has flaws. Namely, tactical drawback: they armed frogmen, if they have to carry on and "land" battle, are required to carry excess weight in the form of more of the 1st machine. On the surface it was a natural decision — to make an amphibious machine, but in fact it was more difficult. On the creation of such two-media system took a lot of hard times, and the first copy of it was presented only in the late 90's. Experiments on the "crossing" the MTA and the AK-74 were conducted in the Tula Design Technological Institute of Engineering (TPKTIMash) under the control of the designer Yuri Danilov. From scuba predecessor, the new machine, named AFM-DT "Sea Lion", was a huge part of parts of the structure, but from a Kalashnikov 5,45 x39 mm and shop. Shutter, the exhaust system and trigger switch from APS on AFM-DT without changes, but has been modified cartridge. In the same pocket, on the basis of which was made MEA was placed newcomer bullet, also similar to the nail, and the blunt end, but the smallest caliber. With 5.6 mm, it was reduced to 5.45. And here's why. Since the machine initially designed as a two-media, the designers took into account his ability to fight in the air. 5,45 x39 mm for common traits claimed rifled barrel, so it was decided to "shrink" the bullet-nail to a size at which it can not just cut into the rifling of the barrel.
Feed system AFM-DT under water carried from machine shops APS (26 rounds). In the air, respectively, are used to store Kalashnikov 74th series (30 rounds). Since these shops, as well as ammunition, have different dimensions, the receiver stores received a very exciting design. If you want to dock the "underwater" store, a special spring-loaded cover (fixed across the bottom receiver on the left side) is put aside, shop inserted at the landing site and latched. If a fighter is going to shoot 5,45 x36 mm, the magazine catch is moving all the way forward, and the spring-loaded lid closes the "extra" part of the receiver window shop. In addition to protecting the machine from mud mechanics, the lid does not latch store move backwards. Another aspect of the two-media is to follow: when fired in the air portion of the propellant gas is routed into the barrel in front of a bullet to purge it from the rest there may be water.
Sights "Sea Lion" in general, similar to the MTA, but you can install optical, night or kollimetornogo sight. Also, the designers have provided seating for under-barrel grenade launchers, tactical flashlight or laser pointer and a bayonet.
All the same, "born" machine amphibious ACM-DT in a series held off. The main complaint concerned the need to operate with 2 types of ammunition and stores. On the basis of the "Sea Lion" on TPKTIMashe began developing a new machine DT. Its main difference from the AFM-DT was the assembly Bullpup.
In 2005, the Tula Instrument Design Bureau unveiled a new universal carrier under the symbol PSP. He, like the last underwater ammunition was made on the basis of the sleeve of a "land" of 5.45 x 39 mm cartridge. Employees were able to enter the PMA in her latest iron bullet weight of 16 gr. Length of bullets — 53 mm. With all of this the designers managed to keep fighting properties of a bullet through a huge extension and flat nose of the bullet. Like the "nail" the PCA and the IPU, the newcomer bullet in the water makes around cavitation pocket. At the same time, the bandwidth of the bullet air behaves as the standard. In addition, the PSP has the same dimensions as a standard 5,45 x39 mm, which can be used not only in a new underwater machine. Also was created cartridge PSP-U with a bronze bullet weighing 8 grams, created for educational purposes.
After the occurrence of CAP team Y. Daniel decided to completely abandon the 2 different weapons for different environments and do automatic anew under a single cartridge. Go with this for the latest version of ADS was elected and a new layout — automatic A-91, designed by Tula KBP early 90's. Automatic amphibious received from A-91 Bullpup general assembly diagrams and a lot of plastic parts. Also, the designers left tube abductor spent cartridges, allowing you to use the machine and right-handers and left-handers. Shutter and trigger also endured heavy configurations, except for improvements in water use. But there was a redesigned vapor system: on the receiver appeared mode switch "water-air. " As the AFM-DT, Td, in the "air"Discards any excess above the water volume of fire powder gas and blows them a bullet in front of the barrel.
Thanks to the dimensions of the cartridge memory bandwidth on the machine shops of ADS used AK-74 to 30 rounds. Including by this DSA can be used not only bandwidth, and ammo 7N6, 7N10, etc., with the difference that the latter can not be used underwater. Underwater ADS properties of ammunition CAP remained at APS — distance of 28-30 meters at a depth of 5 m and 18-20 m at a depth of 20 meters. "Land" of the number, in turn, have grown up and slightly inferior traits Kalashnikov 74 series. Thus, for example, sighting range Td in the air meter 30 is not like APS and 600 all.
In view of the assembly Bullpup, on the machine A-91 and, as a consequence, the ADS is a handle for carrying. It also established an open rear sight. Fly is located on the trunk. On the handle itself can be installed optical, red dot or at least some other compatible sight. Another detail ADS inherited a legacy from the A-91 — built-in 40 mm grenade launcher. Grenade Launcher can use all the modifications grenades VOG-25. The trigger grenade placed under one bracket with the trigger state machine (see photo). If a fighter does not need a grenade launcher, it can be removed from the trunk placed on it sight. If you remove the barrel grenade launcher on the barrel machine can install a device or silencer nozzle blank firing.
So Makar, engineers TPKTIMasha made the whole complex, which has the potential to change immediately several types of special forces weapons: rifles MTA and AK-74M, and grenade launchers GP-25 and GP-30. With all of this single set of ADS, with similar to other types of properties, has advantages in weight and size on one machine with a few details "underweight" to transport and easier to use and easier than going to several different weapons. And it looks like Tula really managed to please the special forces: in 2009, he entered the ADF tests in the special forces of the fleet, and it is clear that the complex has earned many positive reviews.