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Carl-Gustav m/21-m37 (Kulsprutegevar KG m/21-m/37) Light Machine Gun (LMG) / Squad Support Weapon (Sweden)

The Kulsprutegevar KG m/21 and m/37 guns were nothing more than modified Swedish Army versions of the famous American Browning Automatic Rifle.

 Entry last updated on 5/9/2016; Authored by Staff Writer; Content ¬©

  Carl-Gustav m/21-m37 (Kulsprutegevar KG m/21-m/37)  
Picture of Carl-Gustav m/21-m37 (Kulsprutegevar KG m/21-m/37) Light Machine Gun (LMG) / Squad Support Weapon (Sweden)

The Belgian concern of Fabrique National began license production of the famous M1918 Browning Automatic Rifle (BAR) in 1920 and its first export mark became the KG m/21 (or "Kulsprutegevar Model 21") developed to Swedish Army specifications. Like many other nations of the period, the Swedes looked to the M1918 to fulfill the squad automatic weapon role for its value in high volume suppression of enemy positions. The m/21 evolved the base M1918 (as the export "M1919" by Colt) design by adding a pistol grip (as opposed to integral grip along the shoulder stock) and a spiked bipod assembly for support fire. The largest change, however, lay in the conversion of the internals to fire the Swedish Army's 6.5x55mm "Swedish Mauser" cartridge. The 20-round detachable box magazine was retained - a limitation of the M1918 series as a whole.

Initial reactions were positive though the m/21 held a propensity to overheat its barrel assembly through prolonged fire. Thusly, Carl Gustafs Stads Gevarfaktori (now Bofors) took to developing a quick barrel changing function to the m/21 which allowed the operator to replace the barrel by managing a simple latch at the front of the receiver. The attached carrying handle facilitated handling of the hot barrel during the process. The wooden handguard of the original BAR was subsequently dropped. All other BAR functions remained intact. As such, Carl Gustafs ended producing the m/21 under its new designation of KG m/37 in 1937, promptly adopted by the Swedish Army in turn. Older m/21 marks were brought up to the new standard when possible.

By this point, the m/37 now truly fulfilled the light machine gun role, save for its limited 20-round magazine which was never addressed. A prototype belt-fed variant was experimented but never brought to service. Regardless, the m/37 remained in a frontline role until the adoption of the excellent Belgian Fabrique Nationale FN MAG General Purpose Machine Gun of 7.62x51mm NATO standard caliber during the post-World War 2 "Cold War" years. Even then, the m/37 existed in a reserve role within the Swedish Army inventory for a number of years. The FN MAG became widely available in 1958.

Carl-Gustav m/21-m37 (Kulsprutegevar KG m/21-m/37)

Service Year: 1921
Type: Light Machine Gun (LMG) / Squad Support Weapon
National Origin: Sweden
Manufacturer(s): Fabrique Nationale - Belgium / Carl Gustafs Stads Gevarsfaktori - Sweden

Design (Internal, Dimensions and Weights)

Firing Action: Gas-Operated; Tilting Breech Block
Available Caliber(s): 6.5x55mm Swedish Mauser
Ammunition Count / Feed: 20-round detachable box magazine
Overall Length: 1,168 mm (45.98 inches)
Barrel Length: 610 mm (24.02 inches)
Weight (Empty): 21.01 lb (9.53 kg)
Sighting Assist: Iron Front and Rear


Muzzle Velocity: 2,450 feet/sec (747 m/sec)
Rate-of-Fire (RoF): 500 rounds-per-minute (rpm)
Typical Range: 4,500 feet (1,372 meters; 1,500 yards)

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Model Variants (Including Prototypes)

KG m/21 - Fabrique National production of the M1918 Browning Automatic Rifle; Swedish Army requirements included bipod assembly and dedicated pistol grip.
KG m/37 - Update of 1937; quick-change barrel functionality.

Carl-Gustav m/21-m37 (Kulsprutegevar KG m/21-m/37) Images