The 5.45×39mm PSP cartridge is a

rimless A rim is an external flange that is machined, cast, molded, stamped, or pressed around the bottom of a firearms cartridge. Thus, rimmed cartridges are sometimes called "flanged" cartridges. Almost all cartridges feature an extractor or headspacin ...

bottlenecked

intermediate cartridge An intermediate cartridge is a rifle/ carbine cartridge that has significantly greater power than a pistol cartridge but still has a reduced muzzle energy compared to fully powered cartridges (such as the .303 British, 7.62×54mmR, 7.92 ...

. It was introduced into service in 2005 together with

ADS amphibious rifle The ADS (russian: АДС - Автомат Двухсредный Специальный - Special Dual-medium Automatic rifle) is a Russian assault rifle specially made for combat divers. It is of a bullpup layout and is chambered in the 5.45 ...

by Russia. This special cartridge was made for underwater use in ADS rifle and based on standard

5.45×39mm The 5.45×39mm cartridge is a rimless bottlenecked intermediate cartridge. It was introduced into service in 1974 by the Soviet Union for use with the new AK-74. The 5.45×39mm gradually supplemented and then largely replaced the 7.62×39mm car ...

. There are two variants of it. PSP with heavy 16.4g

tungsten Tungsten, or wolfram, is a chemical element with the symbol W and atomic number 74. Tungsten is a rare metal found naturally on Earth almost exclusively as compounds with other elements. It was identified as a new element in 1781 and first isol ...

alloy bullet and PSP-UD with 14.5g bronze bullet.

References

See also