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).
|Designation||12.7 cm/45 (5") SK C/34|
|Ship Class Used On||Germany 1
Destroyers: Z1, Z17 and Z35 classes (Types 1934, 1936 and 1936B)
Torpedo Boats: T61 class, Leopard and Luchs
Training ship: Bremse as rearmed
U-boats: Type XI 2
|Date Of Design||1930|
|Date In Service||1934 3|
|Gun Weight||8,036 lbs. (3,645 kg) 4|
|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||15 - 18 rounds per minute 5|
- ^This weapon was also planned for the Type 1938B Destroyers which never made it off the drawing board.
- ^Guns designed for the Type XI U-Boats weighed 10,196 lbs. (4,625 kg) due to their increased breech end weights.
- ^Converted 10.5 cm (4.1") SKC/28 guns weighed 7,848 lbs. (3,560 kg).
- ^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.
|Weight of Complete Round||N/A|
|Projectile Types and Weights 1a 2a 3a||HE L/4,4 nose fuze 4a: 61.7 lbs. (28.0 kg)
HE L/4,4 nose fuze AA 5a: about 60.2 lbs. (27.3 kg)
ILLUM L/4,5: 60.4 lbs. (27.4 kg)
|Bursting Charge||HE L/4,4 nose fuze: about 4.5 lbs. (2.0 kg) Fp 1 (TNT)
HE L/4,4 nose fuze AA: about 4.5 lbs. (2.0 kg) Fp 1 (TNT)
|Projectile Length||HE L/4,4 nose fuze: 22.2 in (56.5 cm)
HE L/4,4 nose fuze AA: N/A
ILLUM L/4,5: about 22.7 in (57.6 cm)
|Propellant Charge||HE L/4,4 nose fuze: 19.2 lbs. (8.7 kg) RPC/38 (6.4/2.6) or 18.5 lbs. (8.4 kg) RPC/32 (8/4.25)
ILLUM L/4,5: 18.9 lbs. (5.84 kg) Tri RP f. Lg. (9/6) or 12.3 lbs. (5.60kg) RP f. Lg. (6.5/4.5)
|Cartridge Case Size and Weight||128 x 680R mm
HE L/4,4 nose fuze Cartridge - Loaded: 35.3 lbs. (16.0 kg)
ILLUM L/4,5 Cartridge - Loaded: 28.7 lbs. (13.0 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 6a
Leopard and Luchs: 100 rounds
T61: 150 rounds
Type XI U-boats: 270 rounds
Grille and Bremse: N/A
Vasilevs Georgios: 192 rounds
- ^The sources below differ regarding the ammunition used for these weapons. For the most part, I have relied upon the data in M.Dv. Nr. 170,27 and in "German Destroyers of World War Two."
- ^Some sources including "Naval Weapons of World War Two" state that HE base fuze ammunition was supplied for these weapons, but this is not supported by M.Dv. Nr. 170,27 nor by "German Destroyers of World War Two."
Actual German designations HE L/4,4 nose fuze 12,7 cm Spgr. L/4,5 Kz (m.Hb) HE L/4,4 nose fuze AA 12,7 cm Spgr. L/4,5 Kz (m.Hb) – Haube abgeschraubt [unscrewed cap] Illumination L/4,5 12,7 cm Lg L/4,5
- ^There were two versions of the HE L/4,4 nose fuze projectile, these having minor differences in the fuze packaging and very slight differences in the burster weight.
- ^HE nose fuze was also supplied with time fuzes for anti-aircraft purposes. These AA projectiles were the same as the standard HE Nose Fuze projectile, but did not use the ballistic cap (windshield). The 12.7 cm AA projectile was similar to that for the 15 cm/60 (5.9") SK C/25, see the sketch at the bottom of that datapage for details. The designation for these AA rounds was probably 12,7 cm Spgr. L/4,5 Kz (m.Hb) – Haube abgeschraubt - 12.7 cm HE Nose Fuze - Unscrewed [Ballistic] Cap.
- ^Outfits for destroyers were HE nose fuze with and without tracer and 80 illumination rounds per ship.
- Nose fuzed HE was 8.6crh.
- Exercise and practice rounds were produced for this weapon.
- Nammo Raufoss produced an anti-ship projectile (ASP M88) starting in 1989. This projectile had the same interior and external ballistics as the earlier German 12.7 cm rounds and was essentially a scaled up version of the ASP M85 used for former German 10.5 cm/45 (4.1") guns. The projectile weighed 61.7 lbs. (28.0 kg) and had a bursting charge of 7.0 lbs. (3.2 kg).
Many German guns between 12.7 cm and 40.6 cm used HE Nose Fuze projectiles that had ballistic caps [Spgr. Kz (m.Hb)]. As can be seen on the sketch below at left, these projectiles had the impact fuze located on the head of the projectile body, not on the head of the projectile. While improving and simplifying the connection between the fuze and the burster, this approach had a weakness in that the ballistic cap actually "protected" the fuze when the shell made a glancing blow on the target instead of a direct hit. If the fuze was not crushed, the shell often would not detonate.
What the Germans did to improve the likelihood of detonation when the projectile made only a glancing ("graze") hit was to insert a wooden rod, called the Stößel - "Ram" - in these sketches, between the actual nose of the ballistic cap and the fuze. With this design, if the ballistic cap struck something hard enough to deform the cap, even if not a direct hit, then the rod would still be pushed into the fuze and initiate the detonation.
|Range @ 30 degrees||19,030 yards (17,400 m)|
Twin Mount 2b
|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 Rate||Hand operated, only|
"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
"Merkbuch: über die Munition für die 12,7cm SKC/34 in 10,5cm MPL C/28 und 12,7cm MPL C/34" M.Dv. Nr. 170,27 by Oberkommando der Kriegsmarine
Special help from Tony Williams
14 October 2008 - Benchmark
05 June 2011 - Minor additions
12 February 2014 - Changed burster weights
06 February 2019 - Converted to HTML 5 format, reorganized notes, added section on HE Nose Fuze with ballistic caps and added ammunition information and sketches from M.Dv. Nr. 170,27