Germany
20.3 cm/60 (8") SK C/34
Updated 25 May 2015

  This was the only 20.3 cm (8") weapon ever designed by Germany and was quite powerful with a long range.  Two of the turrets intended for the uncompleted Seydlitz were mounted as coastal artillery on Ile De Croix.  It had been intended to mount the other two at Ile de Ré, but this apparently never took place.

These guns are probably best known for when Prinz Eugen started the Boat Deck fire on HMS Hood shortly before her loss.

Four of these guns came into Soviet service when the Germans sold the uncompleted heavy cruiser Lützow to the USSR in 1940.  Renamed Petropavlovsk, only turrets A and D were operational during her early career and she fired 676 rounds in defense of Leningrad.  Badly damaged and sunk in shallow water on 17 September 1941, she was later repaired during 1942 with three working 20.3 cm guns.  She fired over 1,000 rounds during the Leningrad breakout in January 1944.  Renamed Tallin on 1 September 1944.  The Soviets were also interested in purchasing the uncompleted heavy cruiser Seydlitz but this was vetoed by Hitler in 1939.

At the end of World War II, the Prinz Eugen was allocated to the USA.  Before being sent to the nuclear tests in the Pacific, her "A" turret guns were removed at the Philadelphia Navy Yard in Pennsylvania and these were then sent to the Naval Weapons Facility at Dahlgren, Virginia, for testing.  They remain there on permanent display.

Constructed of loose barrel, an inner and outer jacket, a breech end-piece screwed hot on to the outer jacket and a breech block supporting piece pushed into the breech end-piece and held by a threaded ring.  The loose barrel was removable from the rear and would fit any gun.  The breech block was a horizontal sliding type and was hydraulically operated.

Actual bore diameter was 20.30 cm (7.992").

WNGER_8-60_skc34_Prinz_Eugen_aft_pic.jpg

Forward turrets of heavy cruiser Prinz Eugen in 1940

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Click here for additional pictures
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Gun Characteristics
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Designation 20.3 cm/60 (8") SK C/34
Ship Class Used On Germany:  Admiral Hipper and Prinz Eugen Classes
USSR:  Petropavlovsk (later Tallin) (ex-German Lützow)
Date Of Design 1934
Date In Service 1939
Gun Weight 45,636 lb. (20,700 kg)
Gun Length oa 478.4 in (12.150 m)
Bore Length 453.5 in (11.518 m)
Rifling Length 375.1 in (9.527 m)
Grooves (64) 0.094 in deep x 0.227 in (2.4 mm x 5.76 mm)
Lands 0.165 in (4.2 mm)
Twist Increasing RH 1 in 40 to 1 in 35
Chamber Volume 4,272 in3 (70.0 dm3)
Rate Of Fire 4 - 5 rounds per minute
Notes:  Loose liner weighed 12,300 lbs. (5,580 kg) and the breech mechanism weighed 992 lbs. (450 kg).
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Ammunition
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Type Cartridge - Bag
Projectile Types and Weights APC L/4,4 - 269 lbs. (122 kg)
HE L/4,7 base fuse - 269 lbs. (122 kg)
HE L/4,7 nose fuse - 269 lbs. (122 kg)
Illum L/4,5 - 227 lbs. (103 kg)
Bursting Charge APC L/4,4 - 5.1 lbs. (2.30 kg)
HE L/4,7 base fuze - 14.4 lbs. (6.54 kg)
HE L/4,7 nose fuze - 19.7 lbs. (8.93 kg)
Projectile Length APC L/4,4 - 35.2 in (89.5 cm)
HE L/4,7 base fuze - 37.6 in (95.6 cm)
HE L/4,7 nose fuze - 37.5 in (95.3 cm)
Illum L/4,5 - 36 in (91.4 cm)
Propellant Charge Fore Charge:  46.5 lbs. (21.1 kg) RPC/38 (11/4.3)
Main Charge:  65.5 lbs. (29.7 kg) RPC/38 (11/4.3)
Brass case for main charge:  40.1 lbs. (18.2 kg)
Muzzle Velocity All except illum - 3,035 fps (925 mps)
Illum - 2,297 fps (700 mps)
Working Pressure 20.3 tons/in2 (3,200 kg/cm2)
Approximate Barrel Life 300 rounds (one source says 500 rounds)
Ammunition stowage per gun
(see Note 3)
140 rounds
Notes:

1) These guns, like most large caliber German guns, used a "fore charge" which was propellant in a silk bag, and a "main charge" which was propellant in a brass case.  The brass case helped to seal the breech of the gun.

2) Outfits included APC, HE nose fuze, HE base fuze and 40 illumination rounds per ship.

3) This is the design figure.  "German Warships 1815-1945" says that the actual outfit per gun ranged from 120 to 160 rounds.  "Warship Pictorial #21" says that in 1940 the total outfit was 320 APC, 640 HE and 80 starshell and that in 1944 the total outfit was 1,470 shells of mostly HE plus 40 starshells.

4) Ballistic caps for APC and HE had a radius of 10 calibers.

5) Actual Projectile designations were as follows:
   APC L/4,4 - Psgr. L/4,4 (mhb)
   HE L/4,7 base fuze - Spr.gr. L/4,7 Bdz (mhb)
   HE L/4,7 nose fuze - Spr.gr. L/4,7 Kz
   Illumination L/4,5 - Lg. L/4,5

There was also a Spr.gr. L4,7 Bdz (mhb) which had a nose fuze and a windshield, but this may not have entered service.

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Range
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Elevation
With 269 lbs. (122 kg) APC
Striking Velocity
Angle of Fall
Time of Flight
1.9 degrees
5,470 yards (5,000 m)
2,441 fps (744 mps)
2.1
6.0
4.4 degrees
10,940 yards (10,000 m)
1,926 fps (587 mps)
6.1
13.6
8.1 degrees
16,400 yards (15,000 m)
1,519 fps (463 mps)
12.8
23.4
13.3 degrees
21,870 yards (20,000 m)
1,253 fps (382 mps)
23.6
35.9
20.3 degrees
27,340 yards (25,000 m)
1,158 fps (353 mps)
36.8
51.1
29.1 degrees
32,810 yards (30,000 m)
1,191 fps (363 mps)
48.8
69.0
37.0 degrees 
36,636 yards (33,500 m)
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Armor Penetration
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Range With 269 lbs. (122 kg) HE Shell Spr. gr. L/4,7
10,389 yards (9,500 m) 2.0" (5 cm) of Homogenous Armor
Range With 269 lbs. (122 kg) AP Shell Pz. Spr. Ggr. L/4,4
10,400 yards (9,500 m) 9.4" (24 cm) of Face-hardened Armor
18,300 yards (20,000 m) 3.9" (10 cm) of Face-hardened Armor
Note:  The above information is from "German Cruisers of World War Two" for a muzzle velocity of 3,035 fps (925 mps) and is based upon German face-hardened (vertical) and homogenous (deck) armor penetration curves.
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Mount / Turret Data
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Designation Two-gun Turrets
  Admiral Hipper (4) and Prinz Eugen (4):  LC/34
Weight
(see Note 1)
Turrets "A" and "D":  548,951 lbs. (249,000 kg)
Turrets "B" and "C":  577,611 lbs. (262,000 kg)
Elevation
(see Note 2)
Turret "A":  -9 / +37 degrees
Turrets "B", "C" and "D":  -10 / +37 degrees
Elevation Rate 8 degrees per second
Train +145 / -145 degrees
Train Rate 6 - 8 degrees per second
Gun recoil 24.6 in (62.5 cm)
Loading Angle +3 degrees
Notes:

1) Difference in weights was from the thickness of the rear armor and the rangefinders, which were installed only on "B" and "D" turrets.

2) Negative elevation for "A" turret was limited by the shear of the bow.

3) Each turret and mounting had a crew of 72.

4) These mountings generally resembled those for the 38 cm SKC/34 guns used on the Bismarck class except that the fore and main charges were passed by hand to the hoists.  Projectiles and the main charge were rammed hydraulically, but the fore charge was manually loaded.  Other differences were "the use of electrically driven Pittler-Thoma hydraulic gear for auxiliary training, the absence of cartridge-ring cars, both main and fore charges were passed by hand and the presence of two trays in the charge hoist cage with the main charge above the fore." - "Naval Weapons of World War Two."  Auxiliary hoists were simiilar but electric reserve power for the main loading gear was replaced by hand operation.

5) Distance between gun axes was 85.0 in (216 cm).

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Data from
"Naval Weapons of World War Two" by John Campbell
"German Warships 1815-1945" by Erich Gröner
"German Cruisers of World War Two" and "Cruisers of World War Two:  An International Encyclopedia" both by M.J. Whitley
"Warship Pictorial #21:  Kriegsmarine Prinz Eugen" by Steve Wiper
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Special help from Peter Lienau
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Special thanks to Curt Warner, who tracked down the current day whereabouts of the guns from Prinz Eugen's Turret Anton
Other Resources

Additional information about these weapons may be found in the INRO article, The Loss of HMS Hood


Page History

17 January 2007 - Benchmark
19 May 2012 - Updated to latest template
25 May 2015 - Added notes about USSR use and miscellaneous additions