South Korea has revamped their small arms inventory considerably by pursuing weapons of local design, development and production - thus reducing foreign dependency on such war-making goods. This has resulted in a bevy of "K" designated weapons to fulfill various battlefield roles, from assault rifles and machine guns to service pistols and submachine guns. In 1981, the K1 submachine gun was introduced for service and, in 2001, a suppressed version of this weapon followed, this product manufactured by S&T Dawoo (today S&T Motiv). Design work was handled by the Agency for Defense Development and spanned 1998 to 2000..
The K7 differs from the original framework by departing from the gas-operated, direct-impingement system of the K1. Instead, it relies on the tried-and-true blowback action. It also supports the ubiquitous 9x19mm Parabellum pistol cartridge as opposed to .223 Remington, making it more in line with submachine guns of the world. Overall weight is 3.38kg and overall length is 790mm (610mm with the wire stock collapsed). Iron sights are fitted over the receiver in the usual way. The pistol grip is angled rearwards for a firm, ergonomic hold. Over the muzzle of the weapon is a suppressor which extends the length of the weapon from its original K1 form. The weapon feeds from a 30-round detachable box magazine fed into a well set ahead of the trigger group. The thinner profile of the 9mm magazine is apparent when it is loaded into the magazine well which traditionally accommodates the .223 Remington magazine.
Rate-of-fire is 1,100 rounds-per-minute and effective firing ranges reach 150 meters. The typical firing modes are available to the operator - safety, single-shot, three-round burst fire and full-automatic.
Unlike other "suppressed" weapons which attempt to be silent, yet use traditional ammunition in their design along with a silencer, the K7 relies on subsonic ammunition in the 9x19mm Parabellum cartridge along with a silencer to make it a truly silenced weapon. The silencer is used to reduce pressures built up at the muzzle when the gun is fired and this slight delay, in turn, also reduces the sound produced (the telltale "crack") and limits an audible signature - useful when taking out unsuspecting sentries.
The K7 was taken into service by the Republic of Korea Army special forces elements to succeed the in-service Heckler & Kock MP5SD6 series guns. The Korean submachine gun was specifically requested by the service as an economical, indigenously designed alternative to the German offering (which had to be imported at cost). The series has since been adopted by other special forces of the world including Bangladeshi SWADS and Indonesian KOPASSUS operatives.