40mm Bofors

The Bofors 40 mm gun, often referred to simply as the Bofors gun, is an anti-aircraft/multi-purpose autocannon designed in the 1930s by the Swedish arms manufacturer AB Bofors. It was one of the most popular medium-weight anti-aircraft systems during World War II, used by most of the western Allies as well as by the Axis powers. 

Production history

DesignerBofors Defence
ManufacturerBofors Defence (1932–2000)
United Defense Industries(2000–2006)
BAE Systems AB (2006 onwards)


WeightL/60: 1,981 kg (4,367 lb)L/70: 5,150 kg (11,350 lb)
Crewdependent on use
ShellComplete round:
L/60 40×311mmR (1.57 in)
L/70 40×364mmR
Calibre40 mm L/60–70 (actual length varies from 56–70 calibres, based on model)
Carriage522 kg (1,151 lb)
ElevationL/60: -5°/+90° (55°/s)
L/70: -20°/+80° (57°/s)
TraverseFull 360°
L/60: 50°/s
L/70: 92°/s
Rate of fireL/60: 120 round/min
L/70: 330 round/min
Muzzle velocityL/60: 881 m/s (2,890 ft/s)
L/70: 1,021 m/s (3,350 ft/s)
Maximum firing rangeL/60: 7,160 m (23,490 ft)
L/70: 12,500 m (41,000 ft)


Cairns, Qld. Unidentified members, probably of the 10th Australian Light Anti Aircraft Battery, standing around a Bofors 40mm Anti Aircraft gun emplacement opposite a row of houses on a street in Cairns. There is camouflage netting on a frame behind the gun emplacement, probably used to cover the gun when it is not in use. 


Jacquinot Bay, New Britain. Nov 1944. A 40mm Bofors anti-aircraft gun of the 472nd Heavy Anti-aircraft Troop in the Wunung plantation.