The purpose of this article is to provide interested people with all the most important and interesting information regarding such ammunition as cartridge 9x39 SP-6. The history and reasons for its creation, the main characteristics and capabilities. And as a pleasant bonus for true connoisseurs, a brief description of military units using this type of ammunition - all this is collected here and brought to your attention.
History
The history of the SP-6 cartridge dates back to the mid-1980s in the city of Klimovsk, which is located in the Moscow region. The designers of the Central Scientific Research Institute of Precision Engineering (TsNIITochMash) had already worked hard to create a special munition designed for low-noise (silent) shooting. It was known in advance that this type of ammunition will be used by the developed BCC rifle (Special Sniper Rifle, also called the “Vintorez”) and the AS submachine gun (the Special submachine gun, also known as the “Shaft”).
In addition to the basic development requirements, the designers were faced with the task of providing the SP-6 cartridge with sufficient penetration ability at a limited bullet flight speed. This restriction was necessary, since even when firing using noise canceling devices, when a bullet reached 331 m / s, a sonic boom occurred, unmasking the arrow.
Despite the impracticable requirements, several prototypes of ammunition of various designs were developed, however, only the 9x39 mm SP-5 cartridge, developed by designer N.V. Zabelin and technologist L.S., was selected. Dvoryaninova. A little later, the SP-6 modification was released, developed by designer Yu. Z. Frolov and technologist E.S. Kornilova.
The performance characteristics of the cartridge SP-6
The developed modification of the 9x39 SP-6 ammunition had the following characteristics:
- caliber - 9 mm;
- sleeve length - 39 mm;
- total length of the cartridge - 56 mm;
- bullet weight - 16 g;
- cartridge weight - 23 g;
- the amount of gunpowder - 0.6 g;
- bullet flight speed - 305 m / s;
- muzzle energy - 754 J.
The appearance of the ammunition
Consider carefully the cartridge SP-6. In the photo you can notice several interesting details:
- Bullet SP-6 - semi-shell, as evidenced by the black nose of the armor-piercing core, not covered with a bimetallic shell. This significantly helps to distinguish the cartridge of this modification from its ancestor with a single shell.
- If you carefully examine and compare the SP-6 cartridge with the ammunition of a Kalashnikov assault rifle, you will notice a striking similarity between their cartridges. Indeed, when developing cartridges of caliber 9x39, the existing cartridge case from the cartridge 7.62x39 was taken as the basis, but its muzzle had to be expanded to 9 mm in diameter.
Technical features
The design of the SP-6 cartridge is significantly different from its predecessor, however, only the bullet was modified, and the rest of its components remained untouched.
So, what changes have affected the bullet cartridge? To answer this question, we turn to an illustration that clearly demonstrates all of its "insides." As can be seen, the main part of the bullet of the SP-6 cartridge is occupied by the armor-piercing core, while at the same time the core of the predecessor cartridge occupies about a third of the bullet’s internal volume. This design allowed to significantly increase the penetration of the ammunition.
It is important to note that the core material is not known for certain. There are two opinions on this subject: some refer to high-carbon hardened steel (tentatively grade U12), while others refer to the core as being made of heavy-duty tungsten carbide. Which of this is true, and that only a few people involved in the direct development of this cartridge know fiction.
Specifications
As already mentioned, the 9x39 SP-6 cartridge belongs to the armor-piercing class, you need to know what it is capable of. Field-expert gunsmiths claim that the SP-6 bullet fired from VSS Vintorez or Avtomat Val can penetrate 8 mm thick steel sheet (grade and hardness not specified) at a distance of 100 meters. It is also known that the same bullet can hit an enemy protected by an armor plate of 2-3 protection classes at a distance of 300-400 meters.
This means that the hit of the SP-6 shell is equivalent to the hit of a bullet fired from a Kalashnikov assault rifle from a distance of 5 meters. In addition to body armor , armor-piercing cartridges can hit opponents hiding behind a light barrier or inside lightly armored vehicles.
Weapon
The SP-6 cartridge uses at least 9 rifle systems, however, the most interesting are still the VSS Vintorez and AS Val. And they will be discussed:
- Special Sniper Rifle - developed by TsNIITochMash employees in the 80s of the 20th century by order of special forces. Adopted in 1987 and still in use. Due to its design features, high reliability and accuracy, it became very popular during the armed conflicts in the territory of the present Chechen Republic, and the BCC proved to be very good in combat clashes in urban areas, where the use of a standard sniper rifle was less convenient. The rifle, among other things, had a unique "appearance", mainly due to the fixed barrel-muffler and the characteristic shape of a wooden butt. BCC is modular, in other words, it can be disassembled into its components and transported in a more compact form. An ordinary diplomat is quite suitable for such transportation.
- Special machine gun - developed by the same TsNIITochMash based on the already known Vintorez. The differences between these samples of special weapons are not so significant: the “Shaft” is equipped with a folding metal butt, a full pistol grip and a slightly modified automation system, which allowed to increase its life. There is also an option for ammunition from the store for 10 (like BCC), 20 and 30 rounds.
Summary
Cartridges of caliber 9x39, as, incidentally, and the associated samples of special weapons, are, without any exaggeration, outstanding creations of design thought, combining the seemingly contradictory characteristics of penetration ability and speed. The only drawback of this ammunition is the relatively small firing range of 400 meters. This distance, I must say, is very modest for a rifle.
However, do not forget that the cartridge was originally designed with an eye to the requirements of the special services, according to which, first of all, when developing the SP-5 and SP-6 cartridges, it was not the maximum firing range, but the ability to carry out silent shooting without compromising the penetration ability. And no one will argue that the designers did their job with a bang.