In the late 80s, domestic weapons design bureaus began a kind of arms race. The main emphasis in this race was placed on submachine guns, although the engineers did not forget about the submachine guns. In addition, the engineers had a reason: more and more often the special forces of the Ministry of Internal Affairs and the Ministry of Defense spoke negatively about the available weapons, or rather, about its insufficient suitability for certain conditions. For example, the successful and original machine gun AKS74U, which received the unofficial nickname "Ksyusha" among users, gave an indecently large number of ricochets in urban conditions. As a possible replacement for it, new types were offered, such as the SR-3 "Whirlwind" developed by TsNIITochmash or 9A-91 of the Tula KBP. Both samples used cartridges SP-5 and SP-6. These cartridges were chosen because of the subsonic speed (about 280-290 m / s) relative to the heavy bullet (16 grams). For urban conditions, such indicators were considered acceptable.
Simultaneously with work in TsNIITochmash and KBP, new weapons were created in the Tula TsKIB SOO. Shortly before the collapse of the Soviet Union, a weapon complex for special forces OTs-14 "Groza", created for the SP-5 and SP-6 cartridges, had already been developed there. The designers V. Telesh and Yu. Lebedev made the "storm" on the basis of the AKS74U assault rifle, and the shortened Kalashnikov was also chosen as the basic design for the new assault rifle. It should be noted that with a large degree of unification of "Thunderstorms" and "Ksyusha" their designs significantly differed both in the general layout and in a number of some details. The new machine, which received the internal designation OTs-12, and then the nickname "Tiss", decided to make it structurally more similar to the original AKS74U.
As a result of all the work in 1992-93, shooting tests of the new machine began. In accordance with the chosen concept of maximum unification, even outwardly "Tiss" differed little from the base model. The insides were also slightly altered. From the AKS74U, the automatics with a gas engine remained. The barrel is locked by turning the bolt. The latter has a larger cup size compared to the Kalashnikov and is similar to the Groza bolt. Also "Tiss" has a barrel of the appropriate caliber (9 mm) and a new design muzzle, still playing the role of an expansion chamber, but modified to use the new cartridge. The OTs-12 is fed from box magazines for 20 rounds, created at one time for the OTs-14. The Kalashnikov firing mechanism was borrowed without any changes. Accordingly, the principle of operation of the fire safety-translator remained the same. The folding stock, sights, forend and others were transferred to the Tiss from AKS74U almost unchanged, although the lower side of the forend slightly changed its shape, and the sight was redesigned for the ballistics of the new cartridge.
According to the results of the modifications, the OTs-12 differs from the "prototype" only in some numbers: the barrel of the Tula machine gun is shorter (200 mm versus 210 mm), with the expanded buttstock “Tiss” is also shorter by 5 mm (730 versus 735) and is lighter by about 200 grams … The rate of fire of the OTs-12 is higher than that of the shortened Kalashnikov, and amounts to 800 rounds per minute.
Tisse did not manage to achieve much success. With the low cost of manufacturing, he could not normally compete with the 9A91 or "Whirlwind", developed as part of the complexes. As a result, a number of OTs-12s were produced by the mid-90s. It is rather difficult to establish their exact number: some sources speak of several units, in others - about several hundred. The situation is similar with application information. Either the "Tiss" managed to visit only the test site, or it was operated in the special forces of the Ministry of Internal Affairs. However, regardless of the "biography" of the machine, it did not go into a large series and remained an experimental and experimental weapon.
