7.5 cm Leichtgeschutz 40

The 7.5 cm Leichtgeschütz 40 was a recoilless gun used by the German Army during World War II.

7.5 cm Leichtgeschutz 40
Class Manportable
Type Rocket Launcher
Manufacturer Rheinmetall
Production Period 1941 - 1944
Origin Germany
Country Name Origin Year
Germany 1940
Country Name Operational Year Retirement Year
Germany 1940 1945 View
ManufacturerName Production From Production To Quantity
Rheinmetall 1941 1944 450 View

Development of recoilless weapons by Rheinmetall began in 1937 in an effort to provide airborne troops with heavy support weapons that could be dropped by parachute. Both Krupp and Rheinmetall competed for production contracts in a contest that was won by the latter. Initially produced under the designation of LG 1, this was soon changed to LG 40 to match the then current "year of origin" naming system.

One characteristic common to all the German recoilless guns, was that they used ordinary shells, albeit with a different cartridge to cater to the unique issues involved in the recoilless principles.

This gun used HE shells from the 7.5 cm Gebirgsgeschütz (Mountain Gun) 36 and the anti-tank shell of the 7.5 cm Feldkanone 16, neuer Art (Field Cannon, New Model). This meant that its ammunition could not be optimized to benefit from the peculiar ballistic characteristics of recoilless weapons. On the other hand it saved significant research time and effort and meant that existing production lines and stocks of shells could be used at a considerable saving.

Two problems became evident after the Leichtgeschütz (light gun) was fielded. The gas expelled through the venturi of the firing mechanism could cause fouling in the mechanism itself, but fixing this required a redesign of the entire breech and was deemed not worth disrupting the production line or rebuilding the existing guns. The second problem was more serious in that the mounting began to shake itself apart after about 300 rounds were fired. This was principally caused by the torque imparted to the mount when the shell engaged the rifling as well as by the erosion of the nozzles by the combustion gases. These could be countered by welding vanes inside the nozzles that were curved in a direction opposite to the rifling which would then counteract the torque exerted by the shell and minimizing the stress on the gun mount.

Type Recoilless gun
Place of origin Nazi Germany
Service history
In service 1940–45
Used by Nazi Germany
Wars World War II
Production history
Manufacturer Rheinmetall
Produced 1941–44
Number built 450
Specifications
Weight 145 kg (319 lbs)
Length 0.75 m (2 ft 6 in)
Barrel length 458 mm (1 ft 6 in) L/15.5
Shell 75×130 mm. R (HE)
75×200 mm. R (AP)
Caliber 75 mm (2.95 in)
Breech horizontal sliding block
Elevation -15° to +42°
Traverse 360° below 20° elevation
60° above 20° elevation
Rate of fire 8 rpm
Muzzle velocity 350 m/s (1,148 ft/s)
Effective firing range 6,800 m (7,434 yds)

End notes