STK-54

Siinrak Tionsal Kinel 1954
Type	Assault Rifle
Place of origin	Mirhaime Federation
Service history
In service	1954-present (removed from frontline service in 1994)
Production history
Designer	Kilian Mainne Domman nar Giker'ha
Designed	1983
Manufacturer	Reingiker Ardamezou (Reingiker Armory)
Produced	1954-1987
Specifications
Weight	4.0kg (8.8 lbs)
Length	1016mm (40 in)
Barrel length	508mm (20 in)
Cartridge	6.5x42mm M42
Feed system	24-round detachable box magazine
Sights	drum aperture rear sight (adjustable from 200 to 600 m/yd in 100 m/yd increments)

The STK-54 (From Fefsen: Siinrak Tionsal, Kinel 1954, 'Assault Rifle, Type 1954') is a Mirhaimian assault rifle developed by Mirhaimian small arms designer Kilian Mainne Domman nar Giker'ha, and manufactured by Reingiker Ardamezou (Reingiker Armory). It was the standard issued rifle of the Mirhaime Realm Defence Forces from 1954 to 1995 with variants and derivatives still serving within other Mirhaimian uniformed services till this day.

The STK-54 was designed in 1952 by Reingiker Armory at the request of the Mirhaimian Realm Guards to replace the semi-automatic TK-38. The weapon was heavily influenced by contemporary designs, in particular its long stroke piston gas system. Several prototypes were made, and the rifle passed trials in late 1953; proceeding to full manufacturing by 1954. From 1954 to 1987, approximately 1,820,000 rifles (of all variants) were manufactured, and put into service with the Mirhaimian Realm Defence Forces.

In 1955, a derivative of the rifle, the STK-54SA passed Sarvian military and was put into service with the Worker's Armed Forces under the designation of Rk-55A. Approximately 300,000 Rk-55As were manufactured under license by Defense Interprise "Kommunardi" for use by the Sarvian military.

The rifle also saw success within the Mirhaimian civilian sector under the commercial name of M55. According to the Bureau of Firearms, Swords, and Explosive Control (BFSEC), approximately 2,132,000 M55-platform weapons were registered, and in circulation as of 2022; 442,000 of which are fully automatic.

History

ETK-244 Prototype chambered in 6.5x42mm.

The first prototype of the STK-54, the ETK-213, chambered in the standard 6.5x42mm M42 cartridge, was designed in 1949 as a response to the growing number of designs capable of fully automatic firing by Mirhaimian small arms designer Kilian Mainne Domman nar Giker'ha, the designer of the semi automatic TK-38 in service with the Mirhaimian Realm Defence Forces. Domman stated that the Volkian AR series, notably its distinctive gas-operated mechanisms, had a significant influence on the STK-54's design.

The prototype failed to capture the interest of Mirhaimian military commanders at the time, who saw the deployment of such a design to replace the relatively new semiautomatic rifle design in service as unnecessary waste. However, given the apparent efficacy of similar weapons in service with other forces, Domman's prototypes were once again considered in competition with a variety of other designs. With minimal funding from the Guards Infantry Ordnance Board, Domman continued work on the rifle with a small team of engineers towards 1952 when the ETK-244 prototype was presented to the GIOB for testing and field trials.

At the Empress Freida Ke'sed Testing Grounds, the ETK-244 prototype was tested in a competitive service rifle competition conducted by the GIOB. Tests were conducted from the end of the 1952 to the early 1953, and eventually led to the ETK-244 prototype being adopted as the STK-54 with heavy modifications to external components.

By 1993, all STK-54 models were superseded by the STK-92 platform chambered in the newer 6.5x39mm cartridge. The weapon is still kept in service by some rear-line services, including the Artillery and Armored Corps, until around 2007.

The STK-54 (7.62x51mm) was manufactured under license by Defense Interprise "Kommunardi" for use by the Sarvian military.