Pistol SPP-1 complex, designed in the late 1960s, is a personal weapon fighters squad frogmen. It is intended to conduct anti-submarine saboteurs enemy to protect swimmers from sea predators. In the latter case, the gun may be used by persons and civilians. Fire from an underwater gun being only single shots. Complex for underwater shooting SPP-1 was adopted in March 1971.
Work on the creation of the complex were started on proposals from the 1st of the leading designers TSNIITOCHMASH proposal for action in 1968. Designer initiative immediately supported by representatives of the Soviet Navy countersabotage services, which have sponsored. When developing complex simulated an introduction of 2 types of ammunition: active-active and reactive. The research was conducted with the assistance of professionals in branch TsAGI. Ultimately been adopted pistol complex kitted active munition that, despite the fact that the inferior martial features an active-reactive ammunition, different design simplicity. This, in turn, accelerated the process of arms Russian frogmen new tool.
First studies in the field of underwater pistol weapons in our country were launched in 1966. Originality and complexity of the tasks was that the Russian and foreign analogues underwater shooting guns at that time did not exist. In fact, one hundred percent out scientific and theoretical developments such ammunition and guns. The main problem that faced by designers is the inability to develop this underwater gun fire. This was due to the fact that shooting underwater accompanied with 2 negative factors: filling the bore water and the highest density of water, which is 800 times denser than air.
If the highest density of water led to a decrease in resistance of the bullet on the line of motion and decrease the firing range, then filling the trunk led to repeated increase in the pressure of powder gases in the barrel and chamber, exposed to the different moving parts of tools that could lead not only to the destruction of small conventional weapons schemes, and the death of the shooter.
Already at the stage of the first test designers have found that conventional bullet designs using underwater have a very limited range of a shot, because start to lose their effectiveness has been on very small distances (up to 1 meter). It was found that they are one hundred percent not apply to the introduction of underwater small arms. In the coming designers OP Kravchenko and PF Sazonov was chosen constructive scheme underwater cartridge, which was based on the principle of throwing an elongated bullet. Initially, it was possible by means of the theory, and then on the basis of complex research and development work, as in the practical application to create spetsboepripasov for shooting special non-rotating elongated bullets owning hydrodynamic stabilization that was achieved by cavitation bubble that appears when moving Bullet underwater.
Made in TSNIITOCHASH pistol complex consisted of non-automatic pistol Quadruple SPP-1 (then SPP-1M), 4.5-mm ammunition for it, also 3-sealed canisters for 3 clips, holster, synthetic leather, accessories that were equipment designed for ammunition clips, lap belt, oiler and cleaning rod.
Structurally, the gun was designed as a model autoloading classical form with the possibility of a single lamp. Trunk SPP-1 was designed as a single unit, which swings down (on a shotgun offense). Block of 4 trunks fastened on a trunnion frame. In a combat situation it was fixed with a special latch. This circuit is designed to use cartridges great length — 145 mm. Gun had trigger mechanism double act, who was behind the block of 4 trunks and provided alternately shots of each of them. Trigger gun worked from the 1st trigger. At each shot a drummer in a special rotating basis did turn 90 degrees and under the influence of the hammer broke new cartridge cap.
SPP-1 was equipped with a safety lever, which was located on the frame behind and to the left of the trigger guard and had 3 positions, «fuse», «fire», «charge». Translation fuse recently unlocked the top position for the production unit trunks reloading guns. It can be used in gloves. Loading the SPP-1 produced clip in which aggressively been fixed 4 rounds. Clip accelerated the process of recharge guns due to the simultaneous insertion of four rounds in the trunks. After the shots were removed immediately with a holder and cartridge cases. Aiming for a swimmer could use fly and unchanging sight. Pen gun was hollow and made of plastic.
All major parts guns produced stainless steel heat-treatable. Because in comparison with conventional stainless steels possess inflated friction efficiency of the mechanism for the growth of all rubbing parts were covered with a specially designed structure, which came into the molybdenum disulfide. This coating makes the role of a tough and efficient lubrication. Cylindrical coil springs were made of ordinary carbon spring steel and are protected from corrosion resistant lacquer hot drying. Cheeks, who played the role of force element, were made of duralumin alloy, they are protected against corrosion by means of anodization.
Effective range of fire under water using a standard cartridge ATP decreases with increasing depth, but in all cases it was above the range of sight to one or another depth. Implementation of this bullet has provided guarantee defeat of the enemy, dressed in a suit, or attacking swimmer marine predators.
In 1979, the gun was modernized and was designated SPP-1M. He was distinguished by the presence of springs, which facilitates descent and enlarged trigger guard allowed the introduction of combat swimmers special insulated three-fingered gloves. Gun transferred to a special belt holster made of artificial leather, equipped with 12 rounds in the cage were placed in a special iron canisters. Issue 4.5-mm pistol SPP-1M, as well as 5.6-mm machine for underwater shooting APS, was deployed at the Tula Arms Plant. It should be noted that no direct analogue complex weapons combat swimmers are not allowed.
The performance properties of SPP-1M:
Caliber — 4.5 mm;
Chuck — ATP (4.5 × 39 mm)
Pistol length — 244 mm;
Barrel length — 203 mm;
weight of ammunition — 1.03 kg unloaded — 0.95 kg;
the initial velocity of the bullet in the air — 250 m / s;
capacity clips — 4 rounds;
sighting range: at a depth of 40 m — 6 m, at a depth of 20 m — 11 m, at a depth of 5 m — 17 m