23x115mm

The 23×115mm round is used by Soviet (USSR)/Russian/CIS aircraft autocannon, most notably by the GSh-23L and GSh-6-23. Although the round has been superseded by the 30×165mm round, the Russian Air Force still uses it in the GSh-23L (in aircraft's tail turrets and in the UPK-23-250 gunpack/gunpod) and GSh-6-23 (used in Su-24). This round still serves in many countries and is widely available.

History
The round was derived from the 14.5×114mm round by necking it out to 23 mm. The original rounds used a lower power charge of 33 g of sw 4/7 powder and achieved only 690 m/s at a maximum pressure of 294.3 MPa. In 1954 an improved ammunition was introduced, featuring better projectile design and ballistic properties. The newer rounds have a powder charge to achieve 720 m/s.

Weapon platforms

 * Nudelman-Suranov NS-23, used in the An-2, Il-10, Il-22, La-9, La-11, La-15, MiG-9, Yak-7, Yak-9U, Yak-15, Yak-17, and Yak-23 fighters; and in the Mi-2US, Mi-2URN, and Mi-2URP helicopters.
 * Nudelman-Rikhter NR-23, used in the MiG-15, MiG-17, and La-15 fighters.
 * Afanasev Makarov AM-23, used in the Tu-16, Tu-95, Il-54 bombers; and in the An-8, An-12, Il-76 transports.
 * Gryazev-Shipunov GSh-23, used in the MiG-21, MiG-23, SOKO J-22 Orao, HAL Tejas, and IAR 93 fighters; in the Tu-22M and Tu-95 bombers; in the Mi-24V, Mi-24VP, Mi-24VM, Mi-24VN, Mi-24VU, Mi-35, Mi-35M, Mi-35O, and W-3WA Sokół helicopters; and in the Il-76 transport; and in UPK-23-250 and SPPU-22 gunpods.
 * Gryazev-Shipunov GSh-6-23, used in the Su-15, Su-24, MiG-31, and early versions of the MiG-27 fighters.