The CN08 (Cannon 08) is a 120 mm 55-caliber smoothbore tank gun produced by Hyundai WIA. It was indigenously developed by the Agency for Defense Development and WIA (now Hyundai WIA) from 2003 to 2008 for the XK2 development project started in 1995. The development was completed after the field test ended in September 2008.
The CN08 is the main armament of the K2 Black Panther, and the gun barrel is applied with internal chrome plating technology for the large-caliber gun. The gun barrel can endure a high explosive force as a result of the increased stiffness and wear resistance provided by this internal chromium surface. The main components, including the breech ring, breech block and thermal sleeve, are simplified and designed lightly, the gun barrel weighs and the gun mount weighs .
The gun mount is composed of an eccentric hydro-pneumatic recoil system with oil reservoir for the gun barrel and is complemented by a bustle-type autoloader powered by a switched reluctance motor (SRM) combined with a breech controller that automatically opens and closes the gun tube, and it can fire up to 10 rounds a minute.
The maximum permissible pressure of the gun barrel is 744 MPa (108,000 psi), and when the tank gun fires an improved K279 APFSDS, the maximum proof pressure is , and the muzzle velocity is . It depends on the type of ammunition, but the effective firing range of the tank gun is .
The main armament has a dynamic muzzle reference system (DMRS) consisting of a laser reflector, a laser emitter and a vertical sensor unit (VSU). A laser reflector assembly attached to the top of the thermal sleeve is provided to be adapted to a dynamic muzzle reference system to electro-optically measure the accurate position of the muzzle. The mechanical gyroscope type vertical sensor unit, which calculates the lead angle and superelevation in real time to correct the misalignment of the aim, allows the tank to more accurately hit its intended target even when it is maneuvering on irregular terrain.
CN08's 120 mm round is produced in Poongsan Corporation, a South Korean ammunition manufacturer, and can fire 120ÃÂ570 mm NATO tank ammunition.
On July 29 2008, Hyundai Rotem and Otokar signed a contract for technology transfer and design assistance for the Altay Tank Development Project. This contract includes technology transfer and design assistance for systems, armor package, and 120 mm guns required for Altay tank development.
On July 27, 2022, Polish Armaments Group (PGZ) and Hyundai Rotem signed a framework agreement to supply 180 K2s and 820 K2PLs. The agreement will include rapid arms supply and extensive technology transfer from South Korea, and 180 K2s will be produced in South Korea and delivered to Poland from 2022, and 820 K2PLs will be produced in Poland under license from 2026.