This gun was designed as a smaller and lighter version of the
15 cm SK C/25 guns used as the main armament of the - and s. It shared the earlier gun's design with a loose barrel, jacket and breech-piece with a vertical
sliding breech block.
Naval mountings The
Drh. LC/34 twin-gun mount was the most common mount for the gun in the
Kriegsmarine. It was used as the secondary armament of the and s and was planned to equip the proposed
H-class battleships. The mount weighed between , depending on its armor thickness; the Scharnhorst's mounts had between of armor while the Bismarck's had . Maximum elevation was 40°, giving a range of and maximum depression was -10°, while maximum elevating speed was 8° per second. Each mount was designed for full 360° of traverse, but was limited to much less than that by the ship's superstructure. Speed in train was a maximum of 9° per second. The fastest firing cycle was 7.5 seconds, or 8 rounds per minute. Ammunition was supplied by twin hoists between the guns, at the rear of the mount. The was intended to use a lighter version of this mount with thinner armor that only weighed approximately . This may have designated as the
Drh. LC/40, but development ceased when the ships were canceled in 1939. and also carried four single
MPL C/35 mounts that weighed with armor between thick. Each mount could depress -10° and elevate to 35°; this gave a maximum range of . The
MPL C/28 mount used in the s was virtually identical to the newer mount except its
gun shield was smaller so it weighed only .
Army mount Production of carriages for the
21 cm Mörser 18 and the
17 cm Kanone 18 in Mörserlafette exceeded the available number of barrels in 1941 and eight
SK C/28 barrels were adapted for use on the carriages as the
15 cm Schiffskanone C/28 in Mörserlafette. They were converted to
Heer-standard percussion firing. Most guns were replaced by barrels as they became available, but one battery retained them through the beginning of the
Battle of Kursk in July 1943.
Ammunition The
SK C/28 used several different shells depending on its target. The
15 cm Sprgr L/4.6 KZ m Hb weighed and had a muzzle velocity of . It was a nose-fused
HE shell with
ballistic cap with two copper driving band and a lead ring behind them to act as a decoppering device by scraping away any copper residue from the driving band. The
15 cm Sprgr L/4.5 Bd Z m. Hb was a base-fused shell with a ballistic cap and weighed . It was roughly equivalent to the British "Common Pointed" and also used a lead decoppering ring. The
armor-piercing 15 cm Pzgr L/3.8 m Hb shell had a ballistic cap and weighed . All shells used of propellant in an artificial silk bag, housed in a brass cartridge case. An
illumination shell was also available, although details are unknown. ==History==