15 cm Schnelladekanone C/28 in Mörserlafette

The 15 cm SchiffsKanone C/28 in Mörserlafette (SK C/28 in Mrs Laf) was a German heavy gun used in the Second World War.

Development
Production of carriages for the 21 cm Mörser 18 and the 17 cm Kanone 18 in Mörserlafette exceeded available barrels in 1941 and eight naval 15 cm SK C/28 coast defense gun barrels were adapted for use on the carriages. They were converted to Heer-standard percussion firing (see the articles of those guns for details on the design of the carriage).

Operational use
For Operation Barbarossa (the invasion of the Soviet Union), it equipped Artillerie-Abteilung 625. Most guns were replaced by 17 cm barrels as they became available. However, for Case Blue (the German summer offensive in southern Russia), one battery of Artillery Battalion (Artillerie-Abteilung) 767 was still equipped with them. That same battery retained them through the beginning of the Battle of Kursk in July 1943.

Ammunition
The 15 cm SK C/28 in Mrs Laf could not be converted to use the Heer's standard 15 cm ammunition and had to use naval ammunition. These included the 15 cm Sprgr L/4.6 KZ m. Hb., the 15cm Sprgr L/4.5 BdZ m. Hb. and the 15 cm Pzgr L/3.8 m. Hb. The former was a nose-fuzed 45.5 kg HE shell with a ballistic cap. The second was a base-fuzed 44.8 kg HE shell, also with a ballistic cap. The last-named was a standard 45.3 kg armor-piercing shell. Only one 14.1 kg bag of propellant was used in a separate-loading cartridge case.