Rivarossi HR6069 K5(E) railway gun camouflage livery DRG "Robert"

The K5 was the result of a crash program launched in the 1930s to develop a force of railway guns to support the Wehrmacht by 1939. K5 development began in 1934 with first testing following in 1936 at the Firing Test Range R++genwalde-Bad (German: Schie+ƒplatz R++genwalde-Bad) in Farther Pomerania at the South coast of the Baltic Sea. Initial tests were done with a 150 mm barrel under the designation K5M. Production led to eight guns being in service for the Invasion of France, although problems were encountered with barrel splitting and rectified with changes to the rifling. The guns were then reliable until the end of the war, under the designation K5 Tiefzug 7 mm. Three of them were installed on the English Channel coast to target British shipping in the Channel, and proved successful at this task. Towards the end of the war, development was done to allow the K5 to fire rocket-assisted projectiles to increase range. Successful implementation was done for firing these from the K5Vz. A final experiment was to bore out two of the weapons to 310 mm (12.2") smoothbore to allow firing of the Peenem++nder Pfeilgeschosse arrow shells. The two modified weapons were designated K5 Glatt. Several other proposals were made to modify or create new models of the K5 which never saw production. In particular, there were a number of plans for a model which could leave the railway by use of specially modified Tiger II tank chassis which would support the mounting box in much the same manner as the railway weapon's two bogies. This project was finally ended by the capitulation of Germany. The gun was discovered on a railroad siding in the town of Civitavecchia, on 7 June 1944, shortly after the allies occupied Rome. Robert had been partially destroyed by the gun crew before they surrendered.