A slightly more powerful gun than the previous 28 cm SK L/45. The mountings for these guns used electric pumps to drive hydraulic elevation gear while the training was all electric. The famous German/Turkish battlecruiser Goeben/Yavuz carried these guns for fifty years.
The battlecruiser Seydlitz has the unfortunate distinction of having both her after turrets burned out following damage received at Dogger Bank and then one of them burned out again at Jutland (Skagerrak). However, alterations and practices put in place following Dogger Bank are credited with saving German lives at Jutland (Skagerrak).
With the exception of Yavuz, during World War II these guns were used only as coastal artillery. They were then supplied with a lighter shell with a larger propellant charge for increased range. Four of these guns in single Drh LC/37 coastal turrets were employed as the Grosser Kurfürst battery at Pillau, latter at Framzelle, as part of the Channel defenses.
Constructed of A tube, two layers of hoops and a jacket. Used the Krupp horizontal sliding wedge breech block. A total of 36 guns were made.
All German 28 cm guns had an actual bore diameter of 28.3 cm (11.1").
|Designation||28 cm/50 (11") SK L/50|
|Ship Class Used On||Moltke and Seydlitz Classes|
|Date Of Design||1909|
|Date In Service||1911|
|Gun Weight||91,491 lbs. (41,500 kg) 1|
|Gun Length||557.1 in (14.150 m)|
|Bore Length||528.4 in (13.421 m)|
|Rifling Length||445.4 in (11.114 m)|
|Grooves||(80) (2.8 mm D x 6.92 mm W)|
|Twist||Increasing RH 1 in 45 to 1 in 30 at the muzzle|
|Chamber Volume||9,154 in3 (150 dm3)|
|Rate Of Fire||3 rounds per minute 2 3|
- ^The often-seen figure of 149,914 lbs. (68,000 kg) for this weapon actually includes the weight of the Weige (gun cradle).
- ^The hoists could supply three rounds per gun in 51 seconds, including loading and unloading the hoists, and the firing cycle with a strong and well trained crew was about 20 seconds. However, this rate was rarely achieved in battle.
- ^During the Dogger Bank battle in 1915 Seydlitz was in continuous action for two hours. During that time, she averaged a firing rate of one salvo every 42.3 seconds, an impressive performance considering that the guns were hand worked.
|Type||Cartridge - Bag|
|Projectile Types and Weights 1a||World War I
APC L/3,2: 662.9 lbs. (300.7 kg) 2a
HE L/3,6 base fuze: 665.8 lbs. (302.0 kg)
|Bursting Charge||APC L/3,2: 19.74 lbs. (8.95 kg) 2a
|Projectile Length||APC L/3,2: about 35.3 in (90 cm)
HE L/3,6 base fuze: about 39.7 in (101 cm)
HE L/4,4 base and nose fuze: about 48.5 in (123 cm)
|Propellant Charge 5a 6a||Before World War I
N/A (probably RPC/06)
World War I
World War II - before 1942
World War II - after 1942
|Cartridge Case Size and Weight 9a||283 x 1271 mm
Loaded w/RPC/32: 262.3 lbs. (119 kg)
|Muzzle Velocity||World War I: 2,887 fps (880 mps)
World War II: 2,936 fps (895 mps)
|Working Pressure||20.2 tons/in2 (3,180 kg/cm2)|
|Approximate Barrel Life||N/A|
|Ammunition stowage per gun||Moltke: 81 rounds
Seydlitz: 96 rounds for centerline guns and 81 rounds for wing guns
Actual designations for Projectiles APC L/3,2 28 cm Psgr. L/3,2 (m.Hb) HE L/3,6 base fuze 28 cm Spgr. L/3,6 Bdz HE L/4,4 base and nose fuze 28 cm Spgr. L/4,4 Bdz u. Kz (m.Hb)
- ^The weight of the APC L/3,2 appears in most references as 665.8 lbs. (302.0 kg). However, M.Dv. Nr. 190,1A2 lists the schußfertig - "ready for shooting" - weight as 665.8 lbs. (302.0 kg) but a sketch in this document shows the weight as 662.9 lbs. (300.7 kg). It is possible that the burster composition or the AP Cap was changed at some point, reducing the overall weight. I have chosen to use the sketch weight in the above table.
- ^There were at least three different models of the HE L/4,4 base and nose fuze projectile. The one listed here was the heaviest with the others being one or two kilograms lighter. See sketch below.
- ^These guns, like most large caliber German guns of this era, used a "fore charge" which was propellant in a double bag silk case and a "main charge" which was propellant in a brass case. The brass case helped to seal the breech of the gun.
- ^Propellant weights differ in many references and even in official documents such as the M.Dv. Nr. 170 and M.Dv. Nr. 190 series. This seems to be the result of most charges being listed as "zu etwa" which means "to about," implying that the propellant weights were not closely controlled and that differences of a kilogram or so were acceptable. In addition, different loading weights were used depending upon the powder grain size utilized to make up the charge. The weights in this table are for the powder grain specified.
- ^Silk bag for the fore charge weighed 3.3 lbs. (1.5 kg).
- ^I lack the breakdown between the fore and main charges for the RPC/38 propellants used after 1942.
(maximum elevation as built)
|19,790 yards (18,100 m)|
(maximum elevation after 1915)
|Moltke, Seydlitz: 20,890 yards (19,100 m)|
(Goeben elevation 1918)
|23,730 yards (21,700 m)|
The World War I projectiles are described as "having a rather blunt head," resulting in only a slight increase in range for the higher elevations.
|At the Dogger Bank battle in 1915, these guns are credited with penetrating the 5" and 6" (12.7 and 15.2 cm) side armor belts of the British Battle Cruisers.|
Moltke class (5): Drh LC/1908
Seydlitz class (5): Drh LC/1910
Single Coastal Artillery Turrets
|Weight||Drh LC/1908: 437.5 tons (444.5 mt)
Drh LC/1910: (443.5 to 456.7 mt)
|Elevation 1b||All as built: -8 / +13.5
All after 1915: -5.5 to +16.0 degrees
Goeben: First increased to +16.0, then to +22.5 degrees
Coastal artillery: -5 / +50 degrees
|Elevation Rate||Drh LC/1908: 4 degrees per second
Drh LC/1910: N/A
Coastal Artillery: 10 degrees per second with shell loaded
|Train||End Turrets: About +150 / -150 degrees
Beam Turrets: About +80 / -80 degrees
Coastal Artillery: -220 / +220 degrees
|Train Rate||Drh LC/1908: 3.3 degrees per second
Drh LC/1910: 3.0 degrees per second
Coastal Artillery: 4 degrees per second
|Gun recoil||33.1 in (84 cm) 2b|
|Loading Angle||Drh LC/1908: 2 degrees
Drh LC/1910: 2 degrees
Coastal Artillery: 0 degrees
- ^The recoil distance given above is the nominal figure. The absolute, metal-to-metal recoil distance was 35.4 inches (90.0 cm).
- The guns were individually sleeved but could be coupled together by the elevation gear. Guns were hydraulically elevated. Loading, ramming and the breech mechanism were all hand operated. Shell rooms were below the magazines. A post-war British inspection team was impressed by the spacious magazines in Goeben and 'the arrangement transporting the heavy rear charge from the bays to the handling room door being particularly ingenious and easy to manipulate.' The lower shell and charge hoists ran up to a handling room below the gunhouse. The upper shell hoists came up between and behind the guns and the shells were rolled into the shell tray. When the charges came into the gunhouse, the fore charge was removed by hand and placed into the propellant loading tray while the main charge was tilted onto the other part of the tray. Both shell and charge trays were out of the path of the recoiling gun which meant that they could be loaded while the guns were firing, increasing the rate of fire. Trays were then moved to the loading position where they were rammed by hand. See photographs below for details.
- Seydlitz had 62 complete charges ignited during the Dogger Bank battle and both 'C' and 'D' mountings burned out but there was no explosion. Following the Dogger Bank action, German mountings were modified to improve flash protection but this process was not complete at the time of Jutland (Skagerrak). Modifications included double flap doors installed at the beginning and end of the cartridge hoists and new bayonet clasps were added to the cartridge tins used to store the fore charges. In addition, ammunition handling was changed such that the fore charges were kept in the tins until they reached the gun breeches; main charges were kept protected until they were ready to load. Charges were not allowed to pile up in the gunhouse. Finally, all ready ammunition was removed from the gun houses. When Seydlitz was struck and again penetrated at Jutland (Skagerrak) the resulting fire in "C" mounting was much smaller, involving only two main and two fore charges.
- Each turret required 70 men to operate including twelve men for each gun in the gunhouse.
- Magazines were located above the shell rooms.
Armor thickness given in "Naval Weapons of World War One" by Norman Friedman and in "German Battlecruisers of World War One" by Gary Staff Drh LC/1908 Drh LC/1910 Face 9.0 in (23 cm) 9.8 in (25 cm) Sides 7.1 in (18 cm) 7.9 in (20 cm) Rear 9.0 in (23 cm) 8.3 in (21 cm) Roof 2.4 to 3.5 in (6 to 9 cm) 2.8 to 3.9 in (7 to 10 cm)
"Jutland: An Analysis of the Fighting" and "Naval Weapons of World War Two" both by John Campbell
"Skagerrak" by Arno Dohm
"Naval Weapons of World War One" by Norman Friedman
"The King's Ships Were at Sea: The War in the North Sea August 1914 - February 1915" by James Goldrick
"German Warships 1815-1945" by Erich Gröner
"The Big Gun: Battleship Main Armament 1860-1945" by Peter Hodges
"Battleships of World War I" by Peter Hore
"Die Geschichte der deutschen Schiffsartillerie" by Paul Schmalenbach
"German Battlecruisers 1914-18," "German Battlecruisers of World War One: Their Design, Construction and Operations" and "Battle on the Seven Seas: German Cruiser Battles 1914 - 1918" all by Gary Staff
"The Ship that Changed the World: The Escape of the Goeben to the Dardanelles in 1914" by Dan van der Vat
"Admiral von Hipper" by Capt. Hugo von Waldeyer-Hartz
"German Capital Ships of World War Two" by M.J. Whitley
"Vorläufige Beschreibung der 28 cm S.K.L/45, 28 cm S.K.L/50 und 30,5 cm S.K.L/50 in Kst.Drh.L.C.37" M.DV.Nr. 234.6 Berlin 1941, Oberkommando der Kriegsmarine
"Munitionsvorschriften für die Kriegsmarine - Panzersprenggranaten (Psgr)" M.Dv. Nr. 190,1A2 by Oberkommando der Kriegsmarine
"Munitionsvorschriften für die Kriegsmarine - Sprenggranaten (Spgr)" M.Dv. Nr. 190,1A3 by Oberkommando der Kriegsmarine
"Munitionsvorschriften für die Kriegsmarine - Hülsenkartusche" M.Dv. Nr. 190,4A1 by Oberkommando der Kriegsmarine
"Munitionsvorschriften für die Kriegsmarine - Vorkartusche" M.Dv. Nr. 190,4A6 by Oberkommando der Kriegsmarine
U.S. Naval Technical Mission in Europe - Technical Report No. 393-45, September 1945, "Service Major Caliber Projectiles of the German Navy"
Special help from Peter Lienau and Thorsten Wahl
24 April 2008 - Benchmark
11 January 2009 - Added picture of Moltke
26 August 2011 - Added comment about Seydlitz turret burn-outs and additional projectile information
19 May 2012 - Updated to latest template
24 November 2012 - Added details about guns, ammunition and mountings
05 December 2012 - Added amidships picture of Seydlitz
05 March 2019 - Converted to HTML 5 format, reorganized notes and added data and sketches from M.Dv. Nr. 190,1A3, M.Dv. Nr. 190,4A1 and M.Dv. Nr. 190,4A6
20 December 2019 - Additional detail added regarding the changes made to the mounting and ammunition handling procedures following the Dogger Bank battle.
07 March 2020 - Added ammunition information
05 June 2020 - Added Aubrey Houston Bowden collection photographs of Goeben / Yavuz