The 23x152B mm used by the USSR/CIS

CIS

CIS usually refers to the Commonwealth of Independent States, a modern political entity consisting of eleven former Soviet Union republics.The acronym CIS may also refer to:-Organizations:...

 in the VYa-23 Aircraft Gun

Volkov-Yartsev VYa-23

Volkov-Yartsev VYa-23 is a autocannon used on Soviet aircraft during World War II.-Development:In 1940, A.A. Volkov and S.A.Yartsev created an autocannon called TKB-201 for the new 23 mm round. It was intended to be the primary weapon of the Ilyushin Il-2 ground attack aircraft...

 on the Ilyushin Il-2

Ilyushin Il-2

The Ilyushin Il-2 was a ground-attack aircraft in the Second World War, produced by the Soviet Union in very large numbers...

 ground attack aircraft

Ground attack aircraft

Ground-attack aircraft are military aircraft with primary role of attacking targets on the ground with greater precision than bombers and prepared to face stronger low-level air defense...

 and in the 2A7 and 2A14 autocannon

Autocannon

An autocannon or automatic cannon is a rapid-fire projectile weapon firing a shell as opposed to the bullet fired by a machine gun. Autocannons often have a larger caliber than a machine gun . Usually, autocannons are smaller than a field gun or other artillery, and are mechanically loaded for a...

s on the ZU-23 anti-aircraft gun series and ZSU-23-4 "Shilka", among others. Note that the ammunition for the VYa-23 Aircraft Gun

Volkov-Yartsev VYa-23

Volkov-Yartsev VYa-23 is a autocannon used on Soviet aircraft during World War II.-Development:In 1940, A.A. Volkov and S.A.Yartsev created an autocannon called TKB-201 for the new 23 mm round. It was intended to be the primary weapon of the Ilyushin Il-2 ground attack aircraft...

 uses a brass case and is not functionally interchangeable with the steel case ammunition of the modern ZU-23 anti-aircraft gun series. These two weapon systems use different headspace sizes, therefore requiring ammunition of slightly different dimensions.
While it is not in use in the main anti-aircraft weapons of the modern USSR, being replaced by the 30x165mm, it is still in service with the Russian Marines and many other countries.

Specifications:
Dimensions:	23×152 mm Belted
Muzzle Velocity:	970-980 mps (from 2A7 & 2A14)
Bullet Weight:	184-190 grams
Bullet Types:	OZ/OFZ (HEI High explosive incendiary In warfare, High-explosive incendiary is a type of ammunition specially designed to pierce armor, fragment, and ignite readily combustible materials.... ), OZT/OFZT (HEI-T Tracer ammunition Tracer ammunition are bullets that are built with a small pyrotechnic charge in their base. Ignited by the burning powder, the phosphorus tail burns very brightly, making the projectile visible to the naked eye... ), BZ/BZT (API/API-T)
Weapon Systems:	Volkov-Yartsev VYa-23 Volkov-Yartsev VYa-23 Volkov-Yartsev VYa-23 is a autocannon used on Soviet aircraft during World War II.-Development:In 1940, A.A. Volkov and S.A.Yartsev created an autocannon called TKB-201 for the new 23 mm round. It was intended to be the primary weapon of the Ilyushin Il-2 ground attack aircraft... , 2A7, 2A14.
Applications:	ZU-23, ZSU-23-4 "Shilka", BMP-23 BMP-23 The BMP-23 is a Bulgarian infantry fighting vehicle which was first introduced in the early 1980s. Despite its name, the BMP-23 is very different from the BMP-1 and more similar to BMP-2. The hull is based around that of the Soviet 2S1 Gvozdika, but with thicker armour and a more powerful diesel... , BTR-94 BTR-94 The BTR-94 is a Ukrainian amphibious armoured personnel carrier , a modification of the Soviet eight-wheeled BTR-80. The BTR-94's turret BAU-23x2 is larger than the BTR-80's BPU-1 and is fitted with a twin 23x115mm gun 2A7M with 200 rounds, a coaxial KT-7.62 machinegun with 2,000 rounds, six... , others.