Note the triaxial mounting in the picture below. This was intended to be able to compensate for the motion of the ship and so maintain target lock. Unfortunately, this mounting proved to be susceptible to electrical faults as it was not sufficiently waterproofed and the mountings were opened to the weather. These earlier mounts had limited RPC. The "H" class battleships were to have much improved enclosed mounts with full RPC, but these ships were never completed.
An interesting post-war usage of these guns was on the French destroyers Guichen and Châteaurenault. These were the former Italian light cruisers Scipione Africano and Atilio Regolo which were ceded to France in 1948. All of their Italian armament was removed and they were rearmed with six German 10.5 cm/65 guns and ten French 57 mm/60 AA guns. A single twin mounting was also added to the gunnery training ship Albatros.
Earlier guns were of loose barrel construction, but later guns designated as SK C/33 na had a two-piece barrel with a heavier jacket and were considerably lighter. A late war design that was designated as SK C/33 nT had the two pieces redesigned as a forward loose muzzle piece and the rear part as a short loose liner.
10.5 cm/65 SK C/33 Twin Mounting showing the triaxial motion
|Designation||10.5 cm/65 (4.1") SK C/33
10.5 cm/65 (4.1") SK C/33 na
10.5 cm/65 (4.1") SK C/33 nT
|Ship Class Used On||Germany
Capital Ships and Cruisers: Deutschland, Scharnhorst, Bismarck, Admiral Hipper and Prinz Eugen classes
U-Boat Depot Ships: Bauer class
S-Boat Depot Ships: Lüderitz and Nachtigal classes as rearmed
Planned for "H" class battleships, Graf Zeppelin class and Seydlitz aircraft carriers
|Date Of Design||1933|
|Date In Service||1935|
|SK C/33: 10,053 lbs. (4,560 kg)
SK C/33 na: 9,336 lbs: (4,237 kg)
SK C/33 nT: N/A
|Gun Length oa||269 in (6.84 m)|
|Bore Length||249.9 in (6.348 m)|
|Rifling Length||217.8 in (5.531 m)|
|Grooves||(36) 0.051 in deep x 0.2165 in (1.3 mm x 5.5 mm)|
|Lands||0.144 in (3.66 mm)|
|Twist||Increasing RH 1 in 55 to 1 in 35|
|Chamber Volume||446 in3 (7.31 dm3)|
|Rate Of Fire||15 - 18 rounds per minute|
|Note: The earlier loose-barrel weighed 2,370 lbs. (1,075 kg) while the later two-piece barrel for the na weighed 1,653 lbs. (750 kg).|
|Weight of Complete Round||HE - 58.4 lbs. (26.5 kg) (with RPC/32)
HE - 60.3 lbs. (27.35 kg) (with RPC/40)
HE, Incendiary - 51.8 lbs. (23.5 kg)
|Projectile Types and Weights||HE - 33.3 lbs. (15.1 kg)
AP - 34.8 lbs. (15.8 kg)
HE, Incendiary - 34.8 lbs. (15.8 kg)
Illum - 32.4 lbs. (14.7 kg)
|Projectile Length||HE - 18.1 in (45.9 cm)
HE, Incendiary - 17.2 in (43.8 cm)
HE Complete Round - 45.83 in (116.4 cm)
HE, Incendiary Complete Round - 44.96 in (114.2 cm)
(see Note 4)
|11.46 lbs. (5.2 kg) RPC/32
13.34 lbs. (6.05 kg) RPC/40N
|Muzzle Velocity||HE - 2,952 fps (900 mps)
AP - N/A
Illum - 2,133 fps (650 mps)
|Working Pressure||18 tons/in2 (2,850 kg/cm2)|
|Approximate Barrel Life||2,950 rounds|
|Ammunition stowage per gun
(see Note 2)
|Scharnhorst, Bismarck, "H", Graf Zeppelin:
Adm. Graf Spee: 400 - 500 rounds
Admiral Hipper and Prinz Eugen: 420 rounds
1) The above Barrel Life figure is from "German Capital Ships of World War Two." "Battleships: Axis and Neutral Battleships in World War II" credit this weapon with a life of 4,100 rounds. It is possible that these different values are for different mods of this weapon.
2) These are the design figures. "German Warships 1815-1945" says that the actual outfit for Bismarck was 420 rounds and that for Admiral Hipper was 400 rounds.
3) Outfit for warships was HE and HE incendiary, both nose and base fuzed and with or without tracer and illumination. Depot ships included AP rounds in their outfits, but this was rarely carried by warships.
4) As originally introduced, cartridges for these weapons used RPC/32 propellant. RPC/40N was the most common propellant used during World War II.
|Elevation||With 33.3 lbs. (15.1 kg) HE Shell|
|Range @ 45 degrees||19,357 yards (17,700 m)|
|AA Ceiling @ 80 degrees||41,010 feet (12,500 m)|
(see Note 6)
Scharnhorst (7), Lützow (3), Admiral Hipper (6) and Prinz Eugen (6): Dop. L. C/31
Forward mountings (4): Dop. L. C/31
Aft mountings (4): Dop. L. C/37
Forward mountings (6): Dop L. C/37
Aft mountings (2): Dop L. C/31
Graf Zeppelin (4), Seydlitz (5 - as aircraft carrier), Bauer (1), Lüderitz (1) and Nachtigal (1): Dop. L. C/37
"H" (8): Dop. L. C/38
Guichen (3), Châteaurenault (3) and Albatros (1): Dop. L. C/37
|Weight||Dop. L. C/31: 61,300 lbs. (27,805
Dop. L. C/37: 59,646 lbs. (27,055 kg)
Dop. L. C/38: about 97,000 lbs. (44,000 kg)
|Elevation||C/31: -8 / +80 degrees
C/37 and C/38: -10 / +80 degrees
|Elevation Rate||Dop. L. C/31: 10 degrees per second
Dop. L. C/37 and C/38: 12 degrees per second
|Train Rate||Dop. L. C/31: 8.0 degrees per second
Dop. L. C/37: 8.5 degrees per second
Dop. L. C/38: 10 degrees per second (20 degrees per second slew speed)
|Cross Leveling||- 17 / +17 degrees|
|Cross Leveling Rate||Dop. L. C/31: 5 degrees per second
Dop. L. C/37: 8 degrees per second
Dop. L. C/38: 10 degrees per second
|Recoil||Dop. L. C/31: 16.1 in (41 cm) max
Dop. L. C/37: 15.0 in (38 cm) max
Dop. L. C/38: 15.7 in (40 cm) max
1) "Battleships: Axis and Neutral Battleships in World War II" credits the C/37 and C/38 mounts with -15 / +85 degrees elevation.
2) The Dop. L. C/31 was originally developed for the 8.8 cm AA gun used on earlier ships. This mounting was then adapted for use with 10.5 cm guns. This can be distinguished from the later Dop. L. C/37 by its shorter shield.
3) Twin mounts had a crew of six on-mount plus ammunition passers.
4) The guns in the L. C/31 and L. C/37 mountings were in separate cradles. Both mountings were trained via electrically driven hydraulic gear while the elevation and cross-leveling gear were all electric. Elevation was partially RPC and the cross-leveling was fully RPC. The loading gear used an electric motor on the cradle to drive a continuously running roller above the bore with an idler roller in the breech block. These helped to ram the round into the breech. L. C/37 had a fuze setter for each gun mounted near the breech.
5) The Dop. L. C/38 was an all-electric true turret with full RPC and was to have hoists on the outside of each gun supplying rounds horizontally with automatic loading. One long trunk and one short trunk prototype were completed for evaluation, but the production units were cancelled along with the "H" class battleships.
6) The mixing of Dop. L/31 and Dop. L./37 mountings on Bismarck may partially account for her poor showing against British aircraft during her only operational sortie. These mounts had different training and elevating characteristics that were apparently not accounted for in her AA fire control systems. Tirpitz was originally fitted with two Dop. L/31 mounts but these were replaced in late 1941 giving her a uniform battery of eight Dop. L/37 mounts. The Kriegsmarine designated these mountings in their standard fashion for secondaries with starboard mountings being Stb I (forward) through Stb IV (aft) and port mountings being Bb I (forward) through Bb IV (aft).
7) Distance between gun axes:
8) Bismarck and Tirpitz were equipped with a practice gun installed between "C" and "D" turrets. This consisted of a complete breech mechanism and a short barrel.
9) In 1956 - 1957 the French Guichen and Châteaurenault were converted to flotilla leaders and traded their No. 3 mounting for additional accommodation space. Albatros replaced her 10.5 cm mounting with the prototype of the new 100 mm Model 1945 twin mounting.
10 September 2007 - Benchmark
26 January 2009 - Added gun information and ship usage
17 February 2010 - Corrected number of mountings on Scharnhorst, miscellaneous changes
05 June 2011 - Updated data for Tirpitz mountings and added note about practice gun
29 March 2013 - Added information about Châteaurenault
08 October 2015 - Added information about Albatros