By Gordon Arthur

SNT Motiv, South Korea’s best-known small arms manufacturer, announced during Seoul ADEX 2023, held from 17-22 October, that its STC16 carbine had received the nomenclature K13 from the Ministry of National Defense after being selected for use by the country’s Special Warfare Command.

SNT Motiv stated, “The K13 submachine gun, which was selected for the Special Operations Submachine Gun Type II project, was developed with proprietary technology by applying global trends in rifle development, and accuracy and durability were improved based on the latest manufacturing technology.”

“Following the determination of its combat capability last April,” the manufacturer continued, “a supply contract was signed with the Defense Acquisition Program Administration (DAPA), and it is scheduled to be put into service starting in December. Based on this, SNT Motiv plans to invest more actively in research and development for its next rifle business.”

The K13 5.56mm carbine will be allocated to special forces units to replace the badly aging K1/K1A submachine gun that has served more than 40 years. The first units to receive it will be the 13th Special Mission Brigade of the Republic of Korea Army (ROKA), the Special Warfare Flotilla of the ROK Navy, and the Combat Control Team of the ROK Air Force.

South Korea was originally planning to acquire a foreign-made weapon such as the HK416 or SIG MCX for this requirement, but the STC16 was deemed acceptable after it underwent a yearlong evaluation to ensure it met tough military standards. Acquisition of this weapon is a major step forward for ROK special forces, as the K1A was inadequate for the demands of contemporary warfare.

Small Arms Defense Journal understands that some 1,710 K13s have been ordered under an initial contract. While this number is relatively small, it does set a foundation for further sales as the ROK military seeks to field a next generation of carbines, plus it encourages SNT Motiv to actively sell the weapon on the export market.

In terms of nomenclature, “ST” denotes that a weapon is a company offering, while a “K” prefix is only provided once it is officially adopted by the South Korean military. The STC16 is modular, so components such as barrels, handguards and stocks are interchangeable. A suppressor will also be issued as standard. The carbine uses a short-stroke gas-operated piston.

It is chambered in 5.56 x 45mm caliber, and it weighs 6.6 pounds (3kg). The free-floating barrel is available in three lengths: 10.5-inch (265mm), 11.5-inch (292mm) and 14.5 inch (368mm), creating a weapon that measures between 29.5 and 31.9 inches (750 and 810mm) long overall. The weapons being delivered to ROK special forces all possess the 11.5-inch barrel.

MIL-STD-1913 Picatinny rails over the receiver and forend at the 3, 6 and 9 o’clock positions allow various auxiliary devices to be attached, plus there is a foldable iron sight. It has ambidextrous control handles, magazine catches, and charging handles. The extendable stock has five positions, the handguard is compatible with the M4 series, and it is also useable with polymer magazines.

While the STC16/K13 took pride of place on SNT Motiv’s stand at Seoul ADEX 2023, other relatively new weapons on display were the STSM21 submachine gun, the hammerless STP9 pistol, the K15 and K15PARA 5.56mm light machine guns, the STSR23 7.62mm semiautomatic sniper rifle and the K16 7.62mm medium machine gun. The latter was launched last year, and the K15 in 2020.

The aforementioned STSR23 semiautomatic sniper rifle fires 7.62 x 51mm (308 Winchester) rounds. Although its first development phase is completed, a company spokesperson said the sniper rifle will continue to undergo further refinements; the project only commenced earlier this year. The STSR23 weighs 14.3 pounds (6.5kg) and is available with either a 20-inch (508mm) or 24-inch (609mm) barrel to give an overall length of 42.9 or 44.1 inches (1.09m or 1.12m) respectively. The company remains hopeful it will be eventually adopted by the ROK military as a replacement for the K14 7.62mm bolt-action sniper rifle.

The STSR20 12.7mm anti-materiel rifle is also in development as a company project, and a prototype was displayed at the Seoul exhibition. This rifle has a 29-inch (736.6mm) barrel, and it weighs approximately 30.9 pounds (14kg).

Moving on, the STSM21 is a 9 x 19mm submachine gun weighing 6.6 pounds (3kg) for close-quarters battle. Its free-floating barrel length is 8.6 inches (220mm) and, overall, the STSM21 measures 24-26.4 inches (610-670mm) long. SNT Motiv started development of this weapon with delayed blowback operating system in 2021.

The STP9 9mm striker-fired pistol was unveiled at DX Korea 2022, while the one shown at Seoul ADEX 2023 was stamped with the description STP9A. It weighs 1.6 pounds (740g) and has a 4.3-inch (109mm) barrel. Interestingly, it features an M59-compatible magazine, which would permit the ROK military to reuse existing pistol magazines. Although no tender exercise has yet been announced, SNT Motiv is hoping it could potentially replace the K5 pistol widely used by South Korea’s military.

Although SNT Motiv emerged triumphant with its STC16 in the Special Operations Submachinegun Type II program, the earlier Type I project has still not been resolved. This program represents a requirement for nearly 16,000 carbines, and Dasan Machineries, another South Korean small arms firm, had won the tender with its DSAR-15PC. However, DAPA halted this effort in 2021 after it was discovered that Dasan employees “had unauthorized access beforehand to the type of weapons the agency was planning to develop,” according to The Korean Herald.

However, the Type I project was recently reinitiated, and SNT Motiv is expected to submit an improved version of the STC16/K13 for this other carbine competition. Once both the Special Operations Submachinegun Type I and II programs are completed, the MND will doubtlessly look to launch a widespread replacement for ubiquitous K2 and K2C1 assault rifles.