The M-1978 Koksan is a 170 mm self-propelled gun of North Korean design and manufacture. Very little information is available due to the secretive nature of the North Korean government. The designations M-1978 and Koksan were given to the type by US military analysts, as they first became aware of it in that year in Koksan, North Korea. What is known is that it is a 170 mm self-propelled gun of the open turret type. It was first seen publicly during a military parade in 1985. At least one example has been acquired by the United States.
Development
According to Jane's, the Koksan is based on a Chinese Type 59 tank chassis. The 170 mm gun is in an open mount with no superstructure, and is stabilized when firing by two large folding spades at the rear. The gun has a range that would allow it to strike Seoul from the Korean Demilitarized Zone. The 170 mm gun itself is a previously unknown type, possibly Russian coastal-defence or ex-naval weapon, though the Soviet/Russian navies are not known to have used this caliber intermediate between their usual 152mm and 180mm calibers, however the German armed forces during World War II did use 17 cm caliber howitzers, indicating that this weapon may have been designed to use Soviet-supplied stocks of captured German wartime ammunition. The M-1978 version carried no on-board ammunition supply. In 1989, a new version of the Koksan appeared, that was designated the M-1989. The main difference was a lengthened chassis that allows 12 rounds of ammunition to be carried. It carries a crew of four; the remaining four personnel needed to man the gun ride in an accompanying ammunition and support vehicle. Unlike its predecessor, the M-1989 has occasionally been put onpublic display by the North Koreans during parades and news broadcasts.
Deployment
Little is publicly known about how North Korea organizes and deploys its artillery. It has been suggested that M-1978's and M-1989's equipped battalions consist of 12 guns, 20-30 trucks and 150-190 personnel, organized into a battalion headquarters and three batteries with four guns per battery. Battalions are organized into a brigade consisting of 3 to 6 battalions. The brigade has a brigade headquarters and supporting engineer, air-defense and target acquisition units. In 1987, several M-1978s were supplied to Iran, and used during the Iran–Iraq War. When using rocket-assisted projectiles, a range of almost could be achieved, making the weapon the world's longest-ranged field artillery piece at the time. Iranian forces used them to carry out long-range harassment fire against Kuwaiti oil fields. A number of the Iranian guns were subsequently captured by the Iraqis and placed on public display. At least one of these was recovered by US Marines in 2008 from the campus of the University of Anbar.. By the time of US capture, the Koksan chassis had been converted to support a S-23 howitzer.