Germany
12.7 cm/45 (5") SK C/34
Updated 05 June 2011
A low-angle weapon intended for surface action, this gun armed all of the German destroyers built before the start of World War II and a few war-built ones.  There was also a twin mount planned for the never-built Type XI U-boats (U-Kreuzer).

At least eight of these guns were exported to Greece for arming the destroyers of the Vasilevs Georgios class.

Early guns were bored-out versions of the 10.5 cm/55 (4.1") SK C/28.  The production guns were constructed of a loose barrel, jacket and breech end piece with a vertical sliding breech block.

Some of these guns were still in service as of 2003 in coastal defense units in Norway.

All German 12.7 cm guns had an actual bore diameter of 12.8 cm (5.04 in).
WNGER_5-45_skc34_Hans_Lody_pic.jpg

Hans Lody Z10
Hans Lody was one of the few destroyers to survive the war
WNGER_5-45_skc34_Friedrich_Ihn_pic.jpg

Destroyer Friedrich Ihn Z14
WNGER_5-45_skc34_DD_pic.jpg

12.7 cm/45 SK C/34 guns on unidentified destroyer
WNGER_5-45_skc34_sketch.jpg

Diagram from "German Destroyers of World War Two" by M.J. Whitley 
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Gun Characteristics
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Designation 12.7 cm/45 (5") SK C/34
Ship Class Used On
(see Note 1)		 Destroyers:  Z1, Z17 and Z35 classes (Types 1934, 1936 and 1936B)

Torpedo Boats:  T61 class, Leopard and Luchs

Gunboat:  Grille

Training ship:  Bremse as rearmed

U-boats:  Type XI

Greece:  Vasilevs Georgios class
Date Of Design 1930
Date In Service
(see Note 2)		 1934
Gun Weight
(see Note 3)		 8,036 lbs. (3,645 kg)
Gun Length oa 226.8 in (5.760 m)
Bore length 213.8 in (5.430 m)
Rifling Length 178.6 in (4.536 m)
Grooves (40) 0.059 in deep x 0.236 in (1.5 mm x 6.0 mm)
Lands 0.157 in (4.0 mm)
Twist Increasing RH 1 in 35 to 1 in 30
Chamber Volume 744 in3 (12.19 dm3)
Rate Of Fire
(see Note 4)		 15 - 18 rounds per minute
Notes:

1) This weapon was also planned for the Type 38B and Type 40 destroyers.

2) The Type 24 torpedo boats Leopard and Luchs were used to test the prototypes of these weapons and had their 10.5 cm/55 guns replaced in 1932.  Much information was gathered during these evaluations and the improved production version made its service debut in 1934.

3) Converted 10.5 cm (4.1") SKC/28 guns weighed 7,848 lbs. (3,560 kg).  Guns designed for the Type XI U-Boats weighed 10,196 lbs. (4,625 kg) due to their increased breech end weights.

4) This weapon was designed for a ROF of 18 - 20 rounds per minute, but the above figure was typical for well-trained crews.  As these were open mounts, bad weather or Arctic conditions could greatly reduce the ROF.

5) This weapon was also planned for the Type 1938B Destroyers and the Type 1940 (T61) torpedo boats.
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Ammunition
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Type Separate
Weight of Complete Round N/A
Projectile Types and Weights HE - 61.7 lbs. (28.0 kg)
ILLUM - 60.4 lbs. (27.4 kg)
Bursting Charge HE - 18.7 lbs. (8.5 kg)
Projectile Length 22.2 in (56.5 cm)
Propellant Charge 19.2 lbs. (8.7 kg) RPC/38 (6.4/2.6)
Cartridge - 35.3 lbs. (16 kg)
Muzzle Velocity HE - 2,723 fps (830 mps)
ILLUM - 2,133 fps (650 mps)
Working Pressure 18.7 tons/in2 (2,950 kg/cm2)
Approximate Barrel Life 1,950 rounds
Ammunition stowage per gun Z1, Z17 and Z35 classes:  120 rounds
Leopard and Luchs:  100 rounds
T61:  150 rounds
Type XI U-boats:  270 rounds
Grille and Bremse:  N/A

Vasilevs Georgios:  192 rounds
Notes:

1) Outfits for destroyers were nose and base fuzed HE with and without tracer and 80 illumination rounds per ship.

2) Nammo Raufoss produced an anti-ship projectile (ASP M88) starting in 1989.  This projectile has the same interior and external ballistics as the earlier German rounds.  The projectile weighs 61.7 lbs. (28.0 kg) and has a bursting charge of 7.0 lbs. (3.2 kg).

3) HE had a radius of 8.6 calibers.
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Range
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Elevation With 61.7 lbs. (28 kg) HE Shell
Range @ 30 degrees 19,030 yards (17,400 m)
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Mount / Turret Data
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Designation Single Mount
   Germany:  Destroyer Types 1934 (5), 1936 (5), 1936B (5) and 1938B (4), T61 (4), Bremse (4) and Grille (3):  MPLC/34
   Leopard (3) and Luchs (3):  MPLC/28

   Greece:  Vasilevs Georgios (4):  N/A (probably MPLC/34)

Twin Mount
   Type XI U-boats (2):  Drh LC/38
Weight  LC/34:  22,487 lbs. (10,220 kg)
LC/38:  93,035 lbs. (42,200 kg) 
Elevation LC/34:  -10 / +30 degrees
LC/38:  -10 / +40 degrees
Elevation Rate Hand operated, only
Train 360 degrees
Train Rate Hand operated, only
Gun recoil N/A
Notes:

1) The twin mount does not appear to have had the guns individually sleeved.

2) The MPLC/28 mountings were converted from 10.5 cm mountings.
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Data from
"Naval Weapons of World War Two" by John Campbell
"Jane's Ammunition Handbook:  Ninth Edition 2000-2001" edited by Terry J. Gander and Charles Q. Cutshaw
"German Warships 1815-1945" by Erich Gröner
"The German Navy in World War II" by Robert Jackson
"Die Geschichte der deutschen Schiffsartillerie" by Paul Schmalenbach
"German Naval Guns:  1939 - 1945" by Miroslaw Skwiot
"German Warships of World War II" by J.C. Taylor
"German Destroyers of World War Two (2nd Edition)" and "Destroyers of World War Two:  An International Encyclopedia" both by M.J. Whitley
Page History

14 October 2008 - Benchmark
05 June 2011 - Minor additions