7.5 cm Leichtgeschütz 40
Encyclopedia
The 7.5 cm Leichtgeschütz 40 was a recoilless gun used by the German Army during World War II.
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 competition that was won by the latter. Initially produced under the designation of LG 1, this was soon changed to LG 40 to match the current 'year of origin' naming system.
This gun used the 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 couldn't be optimized to benefit from the peculiar ballistic characteristics of recoilless weapons. On the other hand it saved considerable research time and effort and meant that existing production lines and stocks of shells could be utilized at a considerable savings in resources.
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.
where it apparently equipped 2. Batterie/Fallschirmjäger-Artillerie-Abteilung (2nd Battery/Parachute Artillery Battalion). It saw widespread use by German parachute units, both Luftwaffe
and Waffen-SS
for the rest of the war. The 500th SS-Fallschirmjäger Battalion
used 4 during its airdrop on Josip Broz Tito
's headquarters at Drvar.
The German Gebirgsjäger
(mountain infantry) also appreciated its light weight and used a number of them during the battles in the Caucasus Mountains
during the Summer and Fall of 1942.
Background
Development of recoilless weaponsRecoilless rifle
A recoilless rifle or recoilless gun is a lightweight weapon that fires a heavier projectile than would be practical to fire from a recoiling weapon of comparable size. Technically, only devices that use a rifled barrel are recoilless rifles. Smoothbore variants are recoilless guns...
by Rheinmetall
Rheinmetall
Rheinmetall AG is a German automotive and defence company with factories in Düsseldorf, Kassel and Unterlüß. The company has a long tradition of making guns and artillery pieces...
began in 1937 in an effort to provide airborne troops with heavy support weapons that could be dropped by parachute. Both Krupp
Krupp
The Krupp family , a prominent 400-year-old German dynasty from Essen, have become famous for their steel production and for their manufacture of ammunition and armaments. The family business, known as Friedrich Krupp AG Hoesch-Krupp, was the largest company in Europe at the beginning of the 20th...
and Rheinmetall competed for production contracts in a competition that was won by the latter. Initially produced under the designation of LG 1, this was soon changed to LG 40 to match the current 'year of origin' naming system.
Design issues
One characteristic common to all the German recoilless guns was that they used ordinary shells, albeit with different cartridge cases to cater to the unique issues involved in with the recoilless principles.This gun used the 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
7.5 cm FK 16 nA
The 7.5 cm Feld Kanone 16 neuer Art was a field gun used by Germany in World War II. Originally built as the World War I-era 7.7 cm FK 16, surviving guns in German service were rebarreled during the early Thirties in the new standard 7.5 cm caliber...
(Field Cannon, New Model). This meant that its ammunition couldn't be optimized to benefit from the peculiar ballistic characteristics of recoilless weapons. On the other hand it saved considerable research time and effort and meant that existing production lines and stocks of shells could be utilized at a considerable savings in resources.
Two problems became evident after the Leichtgeschütz (light gun) was fielded. The gas expelled through the venturi
Venturi effect
The Venturi effect is the reduction in fluid pressure that results when a fluid flows through a constricted section of pipe. The Venturi effect is named after Giovanni Battista Venturi , an Italian physicist.-Background:...
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
Torque
Torque, moment or moment of force , is the tendency of a force to rotate an object about an axis, fulcrum, or pivot. Just as a force is a push or a pull, a torque can be thought of as a twist....
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.
Operational use
The LG 40 first saw use during the Battle of CreteBattle of Crete
The Battle of Crete was a battle during World War II on the Greek island of Crete. It began on the morning of 20 May 1941, when Nazi Germany launched an airborne invasion of Crete under the code-name Unternehmen Merkur...
where it apparently equipped 2. Batterie/Fallschirmjäger-Artillerie-Abteilung (2nd Battery/Parachute Artillery Battalion). It saw widespread use by German parachute units, both Luftwaffe
Luftwaffe
Luftwaffe is a generic German term for an air force. It is also the official name for two of the four historic German air forces, the Wehrmacht air arm founded in 1935 and disbanded in 1946; and the current Bundeswehr air arm founded in 1956....
and Waffen-SS
Waffen-SS
The Waffen-SS was a multi-ethnic and multi-national military force of the Third Reich. It constituted the armed wing of the Schutzstaffel or SS, an organ of the Nazi Party. The Waffen-SS saw action throughout World War II and grew from three regiments to over 38 divisions, and served alongside...
for the rest of the war. The 500th SS-Fallschirmjäger Battalion
500th SS Parachute Battalion
The 500th SS-Parachute Battalion was the parachute unit of the Waffen-SS.The idea to form a paratrooper unit within the Waffen-SS allegedly came directly from Reichsführer-SS Heinrich Himmler.-Creation:...
used 4 during its airdrop on Josip Broz Tito
Josip Broz Tito
Marshal Josip Broz Tito – 4 May 1980) was a Yugoslav revolutionary and statesman. While his presidency has been criticized as authoritarian, Tito was a popular public figure both in Yugoslavia and abroad, viewed as a unifying symbol for the nations of the Yugoslav federation...
's headquarters at Drvar.
The German Gebirgsjäger
Gebirgsjäger
Gebirgsjäger, in English Mountain Riflemen, is the German designation for mountain infantry. The word Jäger is the traditional German term for rifleman...
(mountain infantry) also appreciated its light weight and used a number of them during the battles in the Caucasus Mountains
Caucasus Mountains
The Caucasus Mountains is a mountain system in Eurasia between the Black Sea and the Caspian Sea in the Caucasus region .The Caucasus Mountains includes:* the Greater Caucasus Mountain Range and* the Lesser Caucasus Mountains....
during the Summer and Fall of 1942.
External links
- "Nazi 75mm Paracannon Has No Kick", April 1944 first report by US news media of 7.5 cm LG40
- Pagina 17 - Heavy Infantry Weapons scroll down to bottom of article for details and excellent photos of LG40
- Lone Sentry section on LG40 short technical article