Dora was the second gun to be produced. It was deployed briefly against Stalingrad, where the gun arrived at its emplacement 15 kilometers (9 miles) to the west of the city sometime in mid-August 1942. It was ready to fire on 13 September. It was quickly withdrawn, however, when Soviet encirclement threatened.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.
In February 1942 Heavy Artillery Unit (E) 672 reorganized and went on the march, and Schwerer Gustav began its long ride to the Crimea. The train carrying the gun was of 25 cars, a total length of 1.5 kilometers. The gun reached the Perekop Isthmus in early March 1942, where it was held until early April. A special railway spur line was built to the Simferopol-Sevastopol railway 16 kilometers (10 miles) north of the target, at the end of which four semi-circular tracks were built specially for the Gustav to traverse. Outer tracks were required for the cranes which would have assembled Gustav.
The siege of Sevastopol was to be the gun’s first combat test. Installation began in early May, and by 5 June the gun was ready to fire. The following targets were engaged:
* 5 June
o Coastal guns at a range of 25,000 m. Eight shells fired.
o Fort Stalin. Six shells fired.
* 6 June
o Fort Molotov. Seven shells fired.
o 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 one of the boats in the bay sunk.
* 7 June
o Firing in support of an infantry attack on Sudwestspitze, an outlying fortification. Seven shells fired.
* 11 June
o Fort Siberia. Five shells fired.
* 17 June
o Fort Maxim Gorki and its coastal battery. Five shells fired.
so they we not fired at london. Their collective contribution is totally negligible to anything represented in AA, but add armies of them as you like.