7.5 Cm L/45 M/32 Anti Aircraft Gun - Background and Design

Background and Design

Around 1930 it became clear that a more modern anti-aircraft gun than the M/16, which had been designed in the later half of World War I, was needed. A number of 76 mm anti aircraft guns had been bought from Bofors in 1928, but were no more modern than the M/16.

In 1932 a new and innovative anti-aircraft gun was designed. Partly based on the M/16, it was mounted on a low-slung trailer with three outriggers. Two of the outriggers folded together for transportation, and two rubber wheels could be mounted. The outriggers could be adjusted in elevation to a limited extent to help place the mount in a horizontal position. The mount allowed for a 360° traverse and an elevation between 0° and 85°. The gun had a muzzle brake to reduce recoil, a hydro-pneumatic recoil cylinder and a gas cylinder to aid the forward movement of the barrel at high elevations. In addition the mount had two heavy springs to counterbalance the barrel, as the entire barrel was mounted ahead of the pivots. The barrel was 45 calibres long and had 28 rifles twisting to the right, like the M/16's barrel. The breech block was also similar to the M/16: a semi-automatic horizontal wedge that the gunner had to open manually to remove the case from the previous shot, but which closed automatically on insertion of a new round.

Like late models of the M/16, the M/32 was equipped to receive gun-laying information from a central sight, and also had a device for automatically adjusting the timing of the fuses on the shells.