APS underwater rifle

Made by the Tula Arms Plant (Тульский Оружейный Завод, Tul'skiy Oruzheynyy Zavod) in Russia, it is exported by Rosoboronexport. Under water, ordinary bullets are inaccurate and have a very short range. The APS fires a 120-millimetre-long (4.7 in), 5.66 mm calibre steel bolt specially designed for this weapon. Its magazine holds 26 rounds. The APS's barrel is not rifled; the fired projectile is kept in line by hydrodynamic effects; as a result, the APS is somewhat inaccurate when fired out of water. The APS has a longer range and more penetrating power than spearguns. This is useful in such situations such as shooting an opposing diver through a reinforced dry suit, a protective helmet (whether air-holding or not), thick tough parts of breathing sets and their harnesses, and the plastic casings and transparent covers of some small underwater vehicles. The APS is more powerful than a pistol, but is bulkier, heavier and takes longer to aim, particularly swinging its long barrel and large flat magazine sideways through water.

The rising threat of attacks by frogmen in naval bases caused various anti-frogman techniques to be developed. In the USSR, one of these techniques was guard frogmen sent to stop the attackers. At first these guard frogmen were armed only with knives and AK-type rifles. The rifle was carried in a waterproof case and could be used only on the surface, so the only effective underwater weapon against enemy frogmen was the knife. The SPP-1 underwater pistol was accepted in 1971, but soon proved to be useful for close-up self-defence rather than in attacking more distant targets. Vladimir Simonov undertook the job of developing an underwater assault rifle. The APS was adopted in 1975. Afterwards, there was lengthy improvement work on the APS. One improvement was fitting a perforated gas pipe with a special shield to break up the emitted gas bubbles, making targeting easier and reducing the visibility of the bubbles, allowing stealthier firing of the weapon. In 2021, Rosoboronexport reported the delivery of APS rifles to a foreign country. Due to the limitations of the APS such as being ineffective when being used outside of water, the ASM-DT was designed to address them.

The initial design of the APS was based on the AK-74. It has a magazine capacity of 26 rounds. The first stage of developing the APS was its cartridge. A 5.45-millimetre (0.215 in) by 39-millimetre (1.5 in) cartridge was lengthened by about 115 millimetres (4.5 in) to fit the sharp-fronted steel bolt. Another cartridge version was designed that contained a miniature rocket, which when fired makes a visible streak in the water.

Azerbaijan Belarus India: Used by MARCOS commandos. Kazakhstan Russia Serbia: by the 82nd River Underwater Demolition Company of the 72nd Brigade for Special Operations Ukraine