Bofors 37 mm anti-tank gun | |
Origin: | Sweden |
Type: | Anti-tank gun |
Is Artillery: | yes |
Used By: | See Operators |
Design Date: | 1934 |
Manufacturer: | Bofors |
Production Date: | 1935 – |
Weight: | 370 kg (816 lbs) |
Length: | 3.04m (09.97feet) |
Part Length: | 1.6m (05.2feet) 45 calibers |
Width: | 1.09m (03.58feet) |
Height: | 1.03m (03.38feet) |
Cartridge: | Fixed QF 37×258 mm R |
Cartridge Weight: | 0.74kg (01.63lb)[1] |
Caliber: | 37 mm (1.45 in) |
Rate: | 12 rounds per minute |
Velocity: | 800–870 m/s (2,625-2,854 ft/s) |
Range: | 4,000 m (4,374 yds) |
Max Range: | 6,500 m (7,108 yds) |
Breech: | vertical sliding-block |
Carriage: | split trail |
Elevation: | -10° to 25° |
Traverse: | 50° |
The Bofors 37 mm anti-tank gun was an anti-tank gun designed by Swedish manufacturer Bofors in the early 1930s originally for Swedish use. It was exported to several countries during the 1930s of which several bought licences to produce it themselves. The gun was used in several conflicts but most of its fame comes from its use in the Spanish Civil War and the Winter War where it was used very successfully against light tanks and armored cars among other targets. Beyond its use as an infantry gun it was also used as the main armament in several armored cars and tanks such as the Dutch M39 Pantserwagen and the Polish 7TP to name a few. As the armor of tanks was increased during World War II the gun very quickly became obsolete as an anti-tank gun but was still used effectively as an infantry support gun for the entirety of the war, and well into the Cold War. This was due to its high fire rate, great mobility and effective high explosive shells.
The gun was initially designed by Swedish manufacturer Bofors, mainly for export purposes. It was likely derived from Rheinmetall's 3,7-cm Tak, the predecessor of 3.7 cm Pak 36.[2] 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 Operation Barbarossa.Even though only one Bofors AT-gun was in action in the invasion of Denmark, it damaged two tanks, and shot the tracks off another tank, before its crew were either wounded or killed by a German tank destroyer which drove over the gun. The gun is now at the Tøjhusmuseet in Copenhagen.
During the Winter War, the Finnish guns were successfully used against Soviet tanks such as T-26, T-28 and BT. However, in the Continuation War the gun was found to be ineffective against the T-34 and KV and was relegated to an infantry support role.
The gun was used to equip the British forces in North Africa, where it made up for the lack of the QF 2-pounder anti-tank guns after the Fall of France. It was often carried portee on the back of a vehicle.
Bofors guns were also employed in World War II by Germany, the Netherlands, Romania, Yugoslavia and USSR, but there are no detailed reports of their use.
When it was introduced, the Bofors 37 mm anti-tank gun was an effective weapon, able to deal with contemporary tanks. Its performance, light weight and high rate of fire made it a popular anti-tank weapon in the pre-war Europe. Introduction of better armored tanks early in World War II, however, made the gun obsolete (as with other similarly performing weapons such as the German 3.7 cm Pak 36 and the United States 37 mm Gun M3).
There were many different ammunition types available for the Bofors 37 mm at gun. It could fire all common types of ammunition and some rare types such as APDS and white phosphorus incendiary.
Type | Projectile | Performance | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Core | Weight | Propellant weight (kg NC 1245) | Power | Muzzle-Vo | Penetration | ||||||||
@ 0° from normal | Impact-Vo | @ 30° from normal | Impact-Vo | @ 45° from normal | Impact-Vo | ||||||||
37 mm sk ptr m/34 slpprj m/38 | AP-T | – | 0.735 kg | 0.205 kg | 330 MPa | 785 m/s | 55 mm at 200 m– – – – | 739 m/s– – – – | 45 mm at 200 m40 mm at 400 m 35 mm at 600 m 32 mm at 800 m 29 mm at 1000 m | 739 m/s– – – – | 33 mm at 200 m30 mm at 400 m 27 mm at 600 m 24 mm at 800 m 22 mm at 1000 m | 739 m/s– – – – | |
37 mm sk ptr m/34 slpgr m/39 | APHE-T | 15 grams of Trotyl | 0.740 kg | 0.217 kg | 280 MPa | 775 m/s | - - | - - | 39 mm at 100 m30 mm at 900 m | - – | - – | - – | |
37 mm sk ptr m/34 slpprj m/49 | APDS-T | 24 mm dart | 1150 m/s | - - - - - - | - - - - - - | 70 mm at 0 m65 mm at 200 m 62 mm at 400 m 58 mm at 600 m 55 mm at 800 m 52 mm at 1000 m | 1130 m/s1100 m/s 1060 m/s 1030 m/s 1000 m/s 970 m/s | - – – – – – | - – – – – – | ||||
37 mm sk ptr m/34 sgr m/43 | HE | 95 grams of Trotyl | 0.680 kg | 0.210 kg | 330 MPa | 805 m/s | - | - | - | - | - | - | |
37 mm sk ptr m/34 slövnprj m/38 | P-AP-T | Spotting charge | 0.728 kg | 0.213 kg | 280 MPa | 790 m/s | - | - | - | - | - | - | |
37 mm sk ptr m/34 övngr m/34 | P-HE | Spotting charge | 0.660 kg | 0.220 kg | 330 MPa | 810 m/s | - | - | - | - | - | - |