Military history

This sales film advertises the Bofors 40mm gun, an anti-aircraft autocannon. Created in the 1930’s by AB Bofors, a Swedish arms manufacturer, it was used largely in WW2 by the western Allied Forces. The film opens with the Bofors crest (:21) and will take viewers through a detailed breakdown of the weapon. This weapon had become the standard anti-aircraft gun during WWII and had been modified to become entirely "tropicalized" (:49) meaning it resisted rust and damage from moisture and fungi. Another modification was the replacement of the original separate electron tube amplifiers with compact units (1:06) which required less space. The transistorized amplifier was built into the center platform (1:23). The connection of the gun was simplified and a diagram is shown of the only two cables now necessary (1:39) for the computer and for power. The amplifier was also shock proof as it had been made into a single unit (1:48) and broken or malfunctioning units were easily replaced (2:05) and these required no time to warm up once a change had been made. The pump motor for the hydraulic system and the driving motor for speed gears are pointed to (2:25). Bofors established a permanent technical training school in order to educate officers and technicians on how to use the gun (2:54). Students of the school watch as different functioning tests are conducted prior to the weapons delivery (3:24). Some of the tests include one on the wheel hub brakes (4:26) as well as on the wheel alignment (4:32). The gun is then taken to the proving grounds where the radius of where rounds are to land is shown (5:03). The ammunition for the Bofors 40 mm is also tested (5:12) and the rounds were comprised of high explosive shells with or without tracers. The full caliber armor piercing (5:23) and reduced caliber armor piercing projectiles follow (5:33). A diagram is then provided of the angles of impact for the various shells (6:40). A new type of powder with low caloric values (6:37) enabled little wear of the barrel. The L60 and L70 shells are shown (6:56) as this gun could be converted to use the L60 shells as well. The tools required for this modification are shown and the barrel would also have to be replaced (7:04). Bofors, based upon their experiments, included testing and instructional materials and proposals for maintenance organization (7:25). The film draws to conclusion as footage of the guns being fired at a Swedish Army firing range play out (7:58) and it ends with the Bofors crest (8:30).

The Bofors 40 mm gun, often referred to simply as the Bofors gun, is an anti-aircraft 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 some captured systems being used by the Axis powers. A small number of these weapons remain in service to this day, and saw action as late as the Persian Gulf War.

In the post-war era, the original design was not suitable for action against jet-powered aircraft, so Bofors introduced a new model of significantly more power, the 40 mm L/70. In spite of sharing almost nothing with the original design other than the calibre and the distinctive conical flash hider, this weapon is also widely known simply as "the Bofors". Although not as popular as the original L/60 model, the L/70 remains in service, especially as a multi-purpose weapon for light armoured vehicles, as on the CV 90.