Daewoo Precision Industries K1

In 1976, the ROKA Special Warfare Command requested a new weapon to replace the old M3 submachine gun. In the following year, ADD launched a project derived from the XB rifle, which started in 1972 to replace licensed M16A1s with indigenous weapons. Under the demands of the ROKASWC, the new submachine gun must acquire greater firepower, light weight, cost effectiveness, and easy access to spare parts. The first prototypes were made in 1980, and entered service in 1981 after series of field test.

But due to the design of its flash suppressor, the K1 exhibited serious problems in service with the ROK armed forces. The original version had excessive recoil, noise, flash, and weak stock due to increase in firepower. These problems caused difficulty in aiming especially during night operation.

These shortcomings were later fixed by the development and adoption of a new flash suppressor, which has three holes in the top right quadrant to limit muzzle flip under rapid fire and reduces flash to one-third of that of the early K1. This new version of K1 is known as the K1A and its production began in 1982. All K1 submachine guns in service were subsequently modified to the K1A standard.

The K1A is often mated with the PVS-4K rail integration System. It is seen as a potential candidate for the "Warrior Platform", a Korean next-generation infantry project.[4]

Most of the time, K1 submachine gun is regarded as a shortened or carbine version of Daewoo Precision Industries K2 assault rifle. However, although the two guns share development history they are very different from each other for the following reasons:

• The development of K1 was completed earlier than that of K2.[5]
• The K1 uses the direct impingement gas system, while the K2 uses AK-47 style gas piston system.[5]
• The K1 has 1-in-12 rifling twist for the early 5.56×45mm M193 or .223 Remington, while the K2 has 1-in-7.3 rifling twist for the newer 5.56×45mm NATO (FN SS109).[5]

The carbine version of K2 named K2C was developed and shown to the public in 2012 by S&T Motiv.

• XK1: Experimental prototype.
• K1: First mass-produced variant. Every K1 has been modified to K1A standard.
• K1A: Second mass-produced enhanced variant.
  • MAX-1: Semi-automatic version of K1A for civilian market.[6]
  • K1A1: Civilian version of K1A with longer barrel.

•  Bangladesh[7]
•  Cambodia: Used by 911 Special Forces Regiment[8] 137 K1As sold.[9]
•  South Korea: Standard-issued submachine gun of the ROK Armed Forces.[1] The competition for replacing K1A is currently undergoing.
•  Papua New Guinea[10]
•  Senegal: Received 280 K1A rifles in 2003.[11]
•  Singapore: 855 K1As sold to Singapore from a SIPRI small arms report in 2019.[9]

The S&T Motiv K2C, an upgraded carbine version of the K2 rifle, was provided to the Republic of Korea Army Special Warfare Command for trial. After a series of tests, K2C was rejected. Instead, the Republic of Korea Armed Forces launched a competition for replacing K1A with new rifle.

• Daewoo Precision Industries K2: related development
• S&T Motiv K2C: rejected after field test
• Daewoo Precision Industries K7: 9×19 Parabellum submachine gun with permanent silencer based on K1A
• S&T Daewoo XK9: suggested 9×19 Parabellum submachine gun prototype to replace K1A used by special forces

Wikimedia Commons has media related to Daewoo K1.

• K1 through K7 images
• S&T Daewoo Homepage