Atlantikwall Regelbau S75 & S80 - 38 cm S.K.C/34 Naval Gun Turret - The ...

Atlantikwall Regelbau S75 & S80 - 38 cm S.K.C/34 Naval Gun - The Adolf Gun Bunker.


S75 is the ammunition depot of the Bunker and
The S80 is the for machine room and room for crew.

The 38 cm SK C/34 naval gun was developed by Germany mid to late 1930s. It armed the Bismarck-class battleships and was planned as the armament of the O-class battlecruisers and the re-armed Scharnhorst-class battleships. Six twin-gun mountings were also sold to the Soviet Union and it was planned to use them on the Kronshtadt-class battlecruisers, however they were never delivered. Spare guns were used as coastal artillery in Denmark, Norway and France. One gun is currently on display at Møvig Fortress outside Kristiansand.

Ammunition
It used the standard German naval system of ammunition where the base charge was held in a metallic cartridge case and supplemented by another charge in a silk bag. Both cartridges were rammed together.

Propellant charge
Main charge: 38 cm HuelsKart34 – GefLdG – 108 kg (238 lb) RPC 38 (16/7)

Fore charge: 38 cm VorKart34 – GefLdG – 104 kg (229 lb) RPC 38 (16/7)

Shell
Four types of shells were used by the 38 cm SK C/34 although the Siegfried-Granate could only be used by the coast defense versions. Almost 40 percent lighter, this latter shell could be fired with a reduced charge at 920 metres per second (3,000 ft/s) out to 40 kilometres (44,000 yd). With a full charge it reached 1,050 metres per second (3,400 ft/s) and could travel 55.7 kilometres (60,900 yd) – over 34 miles.

Naval gun
The data given is according to Krupp datasheet 38 cm S.K.C/34 e WA52-453(e). This gun was mounted in pairs in the Drh.L. C/34e turret which allowed elevation from -5° 30' to +30°. Each gun had an individual cradle, spaced 3.5 metres (11 ft) apart, but they were normally coupled together. In general the turret was hydraulically powered, but the training gear, auxiliary elevation, auxiliary hoists and some loading gear was electrically powered. The turrets weighed 1,048 tonnes (1,031 long tons; 1,155 short tons) to 1,056 tonnes (1,039 long tons; 1,164 short tons), rested on ball bearings on a 8.75 metres (28.7 ft) diameter track, could elevate 6° per second and traverse 5.4° per second. The guns were loaded at +2.5° and used a telescoping chain-operated rammer. According to German manuals the required permanent capacity for the loading equipment for ammunition was 2.5 shells per minute. During testing period at the Baltic Sea the AVKS Report states an output of the ammunition delivery system up to 3.125 shells per minute. Under battle conditions Bismarck averaged roughly one round per minute in her battle with HMS Hood and Prince of Wales.

These guns were modified with a larger chamber for coast defense duties to handle the increased amount of propellant used for the special long-range Siegfried shells. Gander and Chamberlain quote a weight of 105.3 tonnes (103.6 long tons; 116.1 short tons) for these guns, presumably accounting for the extra volume of the enlarged chamber. An armored single mount, the Bettungsschiessgerüst ("Firing platform") C/39 was used by these guns. It had a maximum elevation of 60° and could traverse up to 360°, depending on the emplacement. The C/39 mount had two compartments; the upper housed the guns and their loading equipment, while the lower contained the ammunition hoists, their motors, and the elevation and traverse motors. The mount was fully powered and had an underground magazine. Normally these were placed in open concrete barbettes, relying on their armor, but Hitler thought that there was not enough protection for the guns of Battery Todt emplaced on Cap-Gris-Nez in the Pas de Calais near Wimereux and ordered a concrete casemate 3.5 m (11 ft) thick built over and around the mounts. This had the unfortunate effect of limiting their traverse to 120°. Other C/39 mounts were installed at the Hanstholm fortress in Denmark, and the Vara fortress in Kristiansand, Norway.

Four Drh LC/34 turrets, three of which were originally intended to re-arm the Gneisenau and one completed to the Soviet order, modified for land service, were planned to be emplaced at Paimpol, Brittany and on the Cap de la Hague on the Cotentin Peninsula, but construction never actually began. Construction for two of those turrets was well underway at Blaavand-Oksby, Denmark when the war ended.

how is a Regelbau
Before and during World War II, the Wehrmacht built several standardised bunkers and weapon positions in Germany and German-occupied countries. These buildings were called Regelbau, i.e. standardised buildings.

The Regelbau (German for "standard design") were a series of standardised bunker designs built in large numbers by the Germans in the Siegfried Line (German: Westwall) and the Atlantic Wall as part of their defensive fortifications prior to and during the Second World War.