The Rivarossi K5 gun is a true to scale HO railway model It will work on standard Hornby OO track & so is a great unusual model for British modellers The Krupp K5 series all were consistent in mounting a 21 5 m long gun barrel in a box mounting To track other targets needing greater traverse either a special railway track pointing at the target was laid or for 360 degree traverse a turntable with circular track was constructed with a central jack to raise the gun during traverse & to take some of the enormous weight The Robert bun as modelled by Rivarossi operated in Normandy during 1944 & was involved in the Normandy landings