Bofors 37 mm

Bofors 37 mm anti-tank gun
Polish wz.36 anti-tank gun.
Type	Anti-tank gun
Place of origin	Sweden
Service history
Used by	See Operators
Production history
Designed	1934
Manufacturer	Bofors
Produced	1935 -
Specifications
Weight	370 kg (816 lbs)
Length	3.04 m (10 ft)
Barrel length	45 calibers
Width	1.09 m (3 ft 7 in)
Height	1.03 m (3 ft 5 in)
Shell	37×249 mm. R
Caliber	37 mm (1.45 in)
Breech	vertical block
Carriage	split trail
Elevation	-10° to 25°
Traverse	50°
Rate of fire	12 rounds per minute
Muzzle velocity	800-870 m/s (2,625-2,854 ft/s)
Effective firing range	4,000 m (4,374 yds)
Maximum firing range	6,500 m (7,108 yds)

The Bofors 37 mm gun was an anti-tank gun designed by Swedish manufacturer Bofors in the early 1930s. Licensed copies were produced in a number of countries. The gun was used by some European armies during World War II, mainly at the early stage of the war.

The gun was initially designed by Swedish manufacturer Bofors, mainly for export purposes. The first prototype was built in 1932; the development process continued until 1934. The Netherlands were the first to purchase the gun (order for 12 pieces was placed in 1935) and were followed by many other countries. Licensed copies were produced in Denmark, Finland, the Netherlands and Poland.

The barrel was of monobloc type, with semi-automatic vertical sliding breech block and small muzzle brake. It was mounted on a split trail carriage which had suspension and metal wheels with rubber tires. To give the crew some protection from firearms and shell fragments, the gun was equipped with a 5 mm thick shield, with a folding lower plate.

The Bofors gun saw combat for the first time in Spanish Civil War, where it could easily pierce the armor of contemporary light tanks.

The Polish guns were actively used during the German and Soviet invasion of Poland in 1939. Wołyńska Cavalry Brigade equipped with the Bofors 37 mm antitank gun beat the German Panzer Divisions in one of the first battles of the invasion; the Battle of Mokra. At that time, the armored forces of the Wehrmacht consisted mainly of light Panzer I and Panzer II tanks, which were vulnerable to the Bofors gun. Early models of the Panzer III and Panzer IV could also be penetrated at ranges up to 500 m. After Poland was occupied, most of the guns fell into the hands of the German and Soviet armies. The weapon was proven obsolete by 1941 during the Operation Barbarossa.