Schwerer Gustav (English: ''Heavy Gustav'') and Dora were the names under which the German 80 cm K (E) railway guns were known. They were developed in the late 1930s by Krupp in order to destroy large, heavily fortified targets. They weighed nearly 1,344 tons, and could fire a shell that weighed more than 7 tons at distances up to 37 km (23 miles). Designed in preparation for World War II, they were intended to be used against the Maginot Line. But instead of a frontal assault, the Wehrmacht outflanked the line during the Battle of France. One of the guns was used in Russia at the siege of Sevastopol during Operation Barbarossa. It was destroyed near the end of the war to avoid capture.
It is the largest calibre rifled weapon in the history of artillery and fired the heaviest shells of any artillery piece. It is only surpassed in calibre by the American 36-inch Little David mortar and a handful of earlier siege mortars which all fired smaller shells.
In 1934 the German High Command (OKH) gave to the firm of Krupp of Essen, Germany the problem of designing a gun to destroy the fortresses of the French Maginot Line which was then nearing completion. The gun had to be able to punch through 7 meters of reinforced concrete and an armoured plate 1 meter thick, and do this from a range that kept it out of reach of enemy artillery. Krupp engineer Dr. Erich Müller calculated that the task would require a weapon with a calibre of around 80 cm, firing a projectile weighing 7 tonnes from a barrel 30 meters long. As such the weapon would have a weight of over 1000 tonnes. The size and weight meant that to be at all movable it would need to be supported on twin sets of railway tracks. In common with smaller railway guns, the only barrel movement on the mount would be elevation, traverse being managed by moving the weapon along a curved section of railway line. Krupp prepared plans for calibres of 70 cm, 80 cm, 85 cm, and 100 cm.
Nothing further happened until March 1936, when Hitler visited Essen during which he enquired into the giant guns' feasibility. No definite commitment was given by Hitler, but design work began on an 80 cm model. The resulting plans were completed in early 1937 and approved. Fabrication of the first gun started in the summer of 1937. However, producing such a large weapon proved difficult and it became apparent that the original completion date of spring 1940 would not be met.
Krupp built a test model in late 1939 and sent it to the Hillersleben firing range for testing. Penetration was tested on this occasion. Firing almost vertically, the gun was able to penetrate the specified 7 meters of concrete and 1 meter of armour plate. After the tests were completed in mid-1940 the gun and carriage were removed and probably scrapped. Alfred Krupp personally hosted Hitler and Albert Speer (Minister of Armaments) at the Rügenwald Proving Ground during the formal acceptance trials of the Gustav Gun in the spring of 1941.
The outcome of the tests resulted in orders for two guns. The first round was test-fired from the commissioned gun barrel on September 10, 1941 from a makeshift gun carriage on the Hillersleben firing range. In November 1941, the barrel was taken to Rügenwald where 8 further firing tests took place using the 7,100 kg armor-piercing (AP) shell out to a range of 37,210 meters.
In combat, the gun was mounted on a specially designed chassis, supported by two bogies on two parallel sets of railway tracks. Each of the bogies had 20 axles, giving a total of 40 axles (80 wheels). Krupp christened the gun ''Schwerer Gustav'' (Heavy Gustav) after the senior director of the firm, Gustav Krupp von Bohlen und Halbach.
The ammunition for the gun consisted of a heavy concrete-piercing shell and a lighter high-explosive shell. A super-long-range rocket projectile was also planned with a range of 150 km that would require the barrel being extended to 84 m. This rocket projectile would have enabled the bombardment of England.
In keeping with the tradition of the Krupp company, no charge was made for the first gun. However, they did charge 7 million Reichsmark for the second gun ''Dora'', named after the senior engineer's wife.
In February 1942 Heavy Artillery Unit (E) 672 reorganised and went on the march, and ''Schwerer Gustav'' began its long ride to the Crimea. The train carrying the gun was 25 cars long, a total length of 1 mile (1.6 km). The gun reached the Perekop Isthmus in early March 1942, where it was held until early April. A special railway spur was built to the Simferopol-Sevastopol railway 10 miles (16 km) north of the target, at the end of which four semi-circular tracks were built specially for the ''Gustav''. The siege of Sevastopol was to be the gun's first combat test. Positioning of the gun began in early May, and by June 5 the gun was ready to fire. The following targets were engaged:
- 5 June
- Coastal guns at a range of 25,000 m. Eight shells fired.
- Fort ''Stalin''. Six shells fired.
- 6 June
- Fort ''Molotov''. Seven shells fired.
- The White Cliff: an undersea ammunition magazine in Severnaya Bay. The magazine was sited 30 meters under the sea with at least 10 meters of concrete protection. After nine shells were fired, the magazine was ruined and many of the boats in the bay were damaged.
- 7 June
- Firing in support of an infantry attack on Sudwestspitze, an outlying fortification. Seven shells fired.
- 11 June
- Fort ''Siberia''. Five shells fired.
- 17 June
- Fort ''Maxim Gorki'' and its coastal battery. Five shells fired.
By the end of the siege on July 4th, the city of Sevastopol lay in ruins, and 30,000 tons of artillery ammunition had been fired. Gustav had fired 48 rounds and worn out its original barrel, which had already fired around 250 rounds during testing and development. The gun was fitted with the spare barrel and the original was sent back to Krupp's factory in Essen for relining.
The gun was then dismantled and moved to the northern part of the eastern front, where an attack was planned on Leningrad. The gun was placed some 30 km from the city near the railway station of Taizy. The gun was fully operational when the attack was cancelled. The gun then spent the winter of 1942/43 near Leningrad.
Then it was moved back to Germany for refurbishment. Despite some claims, it was never used in Warsaw during the 1944 uprising, though one of its shells is on display at the Polish Army museum there.
The gun then appears to have been destroyed to prevent its capture sometime before April 22, 1945, when its ruins were discovered in a forest 15 km (9 miles) north of Auerbach about 50 km (31 miles) southwest of Chemnitz.
Dora was the second gun to be produced. It was deployed briefly against Stalingrad, where the gun arrived at its emplacement 15 km (9 miles) to the west of the city sometime in mid-August 1942. It was ready to fire on September 13th. However, it was quickly withdrawn when Soviet encirclement threatened; when the Germans began their long retreat they took ''Dora'' with them. ''Dora'' was broken up before the end of the war, being discovered in the west by American troops some time after the discovery of ''Schwerer Gustav''.
The Langer Gustav was a long cannon with 52 cm caliber and a 43 m barrel. It was intended to fire super-long-range rocket projectiles weighing 680 kg to a range of 190 km. This gave it the range to hit London. It was never completed after being damaged during construction by one of the many RAF bombing raids on Essen.
Landkreuzer P. 1500 Monster Project
The Monster was to be a 2500 tonne mobile, self-propelled platform for a 80-cm K (E) gun, along with two 15 cm sFH 18 heavy howitzers, and multiple MG 151 autocannons. It was deemed impractical, and in 1943 was canceled by Albert Speer. It never left the drawing board and no progress was ever made. It would have easily surpassed the Panzer VIII Maus (Largest and heaviest tank ever built) and the Landkreuzer P. 1000 Ratte (Also canceled, never completed, with only one twin 280mm gun turret completed) in weight and size.
- Internet archive copy of panzerlexikon.de video of Dora loading and firing
- Internet archive copy of panzerlexikon.de video of Dora
- Website with additional information on Dora.
- http://www.aopt91.dsl.pipex.com/railgun/Content/Railwayguns/German/Dora%20index.htm A page with very extensive info on the Schwerer Gustav
- http://members.tripod.com/~fingolfen/superheavy/p1500.html An article on the self-propelled version of the Dora.
- German Artillery of World War Two, Ian V. Hogg. ISBN 1-85367-480-X