M/40 Automatic cannon

The 20 mm maskinkanon M.40 S is an autocannon with a calibre of 20mm of Swedish origin. The weapon was intended as both an anti-tank and anti-aircraft weapon.
History.
The 20mm m/40 followed the same pattern of long-recoil operation as the 25mm and 40mm guns. It was chambered for a unique and quite powerful 20×145R cartridge, and could fire at 360 rpm. On a wheeled AA mounting, it weighed 300 kg, on a low tripod for anti-tank use, it weighed 65 kg (the same gun was used in both installations, and could be switched between mountings). In anti-tank form, it was given the nickname "grasshopper" as it jumped about so much on firing. It was known as the pansarvärnsluftvärnskanon m/40 (PVLV) which translates as "Anti-tank/anti-aircraft gun". The ammunition feed consisted of an exposed 28-round rotary magazine above the gun, which in the AT mounting meant that the sights had to be fixed to the side. It appears that these weapons were only used by the Swedish army, with some 2,700 guns being produced. It was also fitted to about forty PB m/31 armoured cars and to fixed AA and "combination" mountings.