The development of the German V3 weapon, was yet another Third Reich “Vengeance” project aiming to unleash it’s reign across the English Channel and target London from the European mainland. However in contrast to the V1 and V2 projects, this was not going to be a bigger, faster or more destructive ballistic missile, this was going to be a super-cannon.
The smoothbore gun would be able to shoot a large caliber finned shell over a great distance, by firing timed, multiple charges from secundary chambers during the projectile’s passing along the barrel, to add extra velocity. Calculations indicated that the gun would be able to shoot a distance of 160 km.
In 1918 during the First World War the French Army made plans to build a long range multi-chambered cannon as an answer to the German “Paris Gun”. Luckily the war ended that same year and the plans disappeared into the army’s archives. But when Germany invaded France in 1940, the army archives fell into German hands and the plans were picked up by chief engineer August Coenders, designer of the bunker busting “Röchling Shell”, who used the plans to build a 20 mm prototype of the multi-chambered gun using excisting Flak 38 AA gun tubes.
With the help of his employer Hermann Röchling, Coenders succeeded in winning the support of Reichsminister Albert Speer for the project, allowing further development and testing of a first 150mm version of the cannon, starting from May 1943 at Heeresversuchsanstalt Hillersleben (Army proving ground) Germany. Speer in his turn informed Hitler about the gun, who gave his enthusiastic assent and ordered full priority for the development and deployment of this “Englandkanone”, even though it was still just a prototype and no results of test firings were available.
Construction of V3 bunker at Mimoyecques and Pumpwerk Misdroy
Although the Coenders design at Hillersleben soon exposed it’s flaws (there were problems with the premature explosion of the charges, the projectile’s design and a disappointing muzzle velocity), it was decided to go ahead with the selection and planning of a suitable site for the gun(s) to target England, leading to the construction of the underground V3 fortress at Mimoyecques, France in September 1943, while the test-facilities for the cannon were expanded to Laatziger Ablage, Misdroy, near the V1 and V2 testfacilities at Heeresversuchsanstalt Peenemünde.
At Laatziger Ablage the construction of three* “Abschussrampe” or test ramps, named Stellung Nord, -Mitte and -Süd, started the same year under the codename “Pumpwerk Misdroy” (eng: Pumping station Misdroy) with the gun ramps being codenamed “Hochdruckpumpe” (eng: High pressure pumps) or simply “HDP” in short. The reason for the selection of the testgrounds at Misdroy was that the cannon needed a certain angle to reach the calculated distance. The steep hillsides at Laatziger Ablage (then Germany, now named Zalesie in Poland) were an ideal setting for this to be achieved.
*There are speculations that there might have been a fourth position or “Stellung”.
Heereswaffenamt takes over
By Januari 1944, the first 150 mm HDP cannons were operational and the next round of test firing started. But in March 1944, when it became clear that Coenders still did not manage to solve the design issues, HWA (Heereswaffenamt) took over the lead of the project. Other companies were brought in to shed their light over the problems in the HDP design and by May 1944 solutions had already been found for the premature initiation of secundary charges by adding a sealing piston before the shell and even a suitable projectile was found, the finned 150 mm Sprenggranate 4481 (97kg). An attempt was made to gain muzzle velocity by placing the chambers of the secundary charges along the barrel under an angle of 45°.
Again tests were done and at first the results seemed to be more promising. During a trail near the end of May 1944, ranges of up to 88 km were registered and in July the projectile even reached 93 km! Unfortunately during these tests, two sections of the gun barrel ruptured and further testing at Laatziger Ablage was cancelled.
Serious questions arose at HWA about further development, as it became clear that a lot of time and effort would be needed before the V3 weapon could effectively be used in the field. Eventually the project was given to SS Obergruppenführer Hans Kammler, who was also in charge of the V1 and V2 programs.
Visit Bunkier V3 Museum
This is not a standard museum, but reminds us of the home of a hardcore WW2 collector (right after his wife left him). The people here are really friendly, there is a nice atmosphere and inside the bunker there is lots of stuff that is worth a look. Don’t expect everything on display to be connected to the history of Laatziger Ablage though, because we highly doubt that. When you just got back from the climb up the hill to see the V3 Ramps, you can buy a refreshment at the kantyna and hang out in front of the bunker. Bring mosquito repellent in the summer though, especially when you take the walk up into the forest.
For more information about the museum visit: www.bunkierv3.pl