These
28 cm SK L/40 guns were used as the main armament of the and
pre-dreadnought battleships, but they were transferred to the
Army from the Navy (
Kaiserliche Marine) when those ships began to be relegated to training duties in 1916 after the
Battle of Jutland had proved that they were not suitable for contemporary naval combat. One change made for land service was the fitting of a large
counterweight just forward of the trunnions to counteract the
preponderance of weight towards the
breech. This, although heavy, was simpler than adding
equilibrators to perform the same function. In 1917, the first four guns, formerly used on , were placed in firing platform (
Bettungsschiessgerüst) mountings for coast defense duty as part of
Batterie Graf Spee on the island of
Wangerooge. The firing platform was a semi-portable mount that could be emplaced anywhere after several weeks of labor to prepare the position. It rotated on a pivot at the front of the mount. The rear was supported by rollers resting on a semicircular rail and was generally equipped with a
gun shield. Twenty guns, from the battleships , , , , , and were mounted on the railroad and firing platform (
Eisenbahn und Bettungsschiessgerüst) (
E. u. B.) mounts successfully used by other German railroad guns. The
E. u. B. could fire from any suitable section of track after curved wedges were bolted to the track behind each wheel to absorb any residual recoil after the gun cradle recoiled backwards. It also had a pintle built into the underside of the front of the mount. Two large rollers were fitted to the underside of the mount at the rear. Seven cars could carry a portable metal firing platform (
Bettungslafette) that had a central pivot mount and an outer rail. It was assembled with the aid of a derrick or crane, which took between three and five days, and railroad tracks were laid slightly past the firing platform to accommodate the front bogies of the gun. The gun was moved over the firing platform and then lowered into position after the central section of rail was removed. After the gun's pintle was bolted to the firing platform's pivot mount, the entire carriage was jacked up so that the trucks and their sections of rail could be removed. The carriage was then lowered so that the rear rollers rested on the outer track. Concrete versions were also used. It could have up to 360° of traverse.
Ammunition Ammunition was moved by means of an overhead rail from which a shell trolley carried individual shells to be placed in the loading tray fixed to the
breech. An extensible rail could be raised and braced in place to allow the shell trolley to reach shells placed on the ground or in an ammunition car behind the mount. This ammunition car sometimes had its own overhead rail to move the shells forward to where the trolley in the mount could reach it through a hatch in the roof. The shell and powder were manually rammed into the gun. The gun had to be loaded at zero elevation and thus needed to be re-aimed between each shot. It used the 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 which was rammed first. == Combat history ==