German Naval Guns Extract

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GERMAN NAVAL GUNS 1939-1945

Seaforth PUBLISHING

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Contents Introduction

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Heavy Guns 2.

The 40cm SK C/34 Guns of Battleships ‘H’, ‘J’, ‘K’, ‘L’, ‘M’ and ‘N’

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3.

The 38cm SK C/34 Guns of the Battleships Bismarck and Tirpitz

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4.

The 28cm SK C/28 Guns of the Deutschland class ‘Pocket Battleships’

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5.

The 28cm SK C/34 Guns of the Scharnhorst class Battleships

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Medium Guns 6.

The 20.3cm SK C/34 Guns of the Admiral Hipper class Heavy Cruisers

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7.

The 15cm SK L/45 Guns of the Cruiser Emden

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8.

The 15cm SK C/25 Gun:

9.

Aboard ‘K’ class Cruisers

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Aboard the Cruiser Leipzig

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Aboard the Cruiser Nürnberg

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The 15cm SK C/28 Gun: Aboard Deutschland class ‘Pocket Battleships’

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Aboard Scharnhorst class Battleships

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Aboard the Aircraft Carrier Graf Zeppelin

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In DrhL C/34 Turrets aboard Scharnhorst and Gneisenau

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In DrhL C/34 Turrets aboard Bismarck and Tirpitz

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10. The 15cm Tbts K C/26 gun aboard Destroyers

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11. The 12.7cm SK C/34 Gun aboard Destroyers

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105mm and 88mm Guns 12. Introduction

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13. 105mm Guns: Single Mounts

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Twin Mounts

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14. 88mm Guns: The 8.8cm SK C/31 Gun

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The 8.8cm SK C/30 Gun in Single Pedestal Mounts

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The 8.8cm SK C/30 Gun in Twin Pedestal Mounts

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The 8.8cm SK L/45 Gun in MPL C/13 Single Pedestal Mounts

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Light Anti-Aircraft Guns 15. Introduction

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16. The 4cm Flak 28 Bofors Gun

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17. 3.7cm Guns

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18. 2cm U-Boat Turrets

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19. 2cm Guns

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Index

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3 THE 38cm SK C/34 GUNS OF THE BATTLESHIPS BISMARCK AND TIRPITZ he design of this gun was based on the 38cm SK C/13 of the First World War. The old design was thoroughly revised, and following the necessary field tests and trials, the new gun was approved for series production as the 38cm SK C/34. Although it was the same calibre as the guns that had armed the Badenclass battleships, the barrel was 6.03 calibres longer, at 48.43 calibres. This, together with other modifications to both the gun and its mounts, gave improved accuracy and greater range. The increased muzzle velocity imparted by the longer barrel improved the trajectory of the shell, making the gun perfectly suited to the type of naval engagement fought in the North

T Below: Fitting-out of the after compartments on Bismarck, 1938. The third armoured bulkhead in the foreground, with the barbettes for ‘C’ and ‘D’ turrets behind it.

(Blohm & Voss via Jörg Schmiedeskamp)

38cm SK C/34 gun Calibre: Weight of gun: Overall length: Length bore: Length chamber: Volume chamber: Length rifling: Grooves: Weight projectile: Propellant charge: Muzzle velocity: Working pressure: Approximate service life: Maximum range:

380mm 111,000kg 19,630mm 18,405mm 2,230mm 319dm3 15,982mm 90 (4.5mm x 7.76mm) 800kg 212kg of RP C/38 (17/7) 820mps 3,200kg/cm2 250 effective rounds 35,550m at 30°

Sea. Elevation was limited to 30°, which was considered more than sufficient at the time the ships were designed. It was believed that future actions would take place at ranges where only 20° of elevation would be required, although an extra 10° was allowed for to accommodate the rolling of the ship in the stormy North Atlantic.

The guns of Battleships ‘F’ and ‘G’ (as Bismarck and Tirpitz were originally designated) were mounted in four twin turrets, a layout which gave a more efficient broadside. The guns, their mounts and the turrets were all designed and built by Krupp’s. After consultations with the Kriegsmarine and once the details of the project had been approved, Krupp’s designer decided to build the turrets with the armour plates bolted on to the framework.

The gun The Krupp 38cm SK C/34 had a vertical sliding breech block. The main propellant charge was contained in a 420mm-diameter brass case – larger than the diameter of the projectile – and, once removed from the ammunition hoist, it was chambered by a single stroke of the hydraulic rammer. The complete firing cycle – chambering the shell and charges, firing and ejecting the empty case – took eighteen seconds.

The Drehscheiben-lafette C/34 (DrhL C/34) turret

Range and ballistic data for 800kg projectiles Range 5,000m 10,000m 15,000m 20,000m 25,000m 30,000m 35,000m

Elevation 2.2° 4.9° 8.1° 12.1° 16.8° 22.4° 29.1°

Angle of descent 2.4° 5.8° 10.4° 16.4° 23.8° 31.9° 40.3°

Flight time 6.5 sec 13.9 sec 22.3 sec 32.0 sec 43.0 sec 55.5 sec 69.9 sec

Velocity 727mps 641mps 568mps 511mps 473mps 457mps 462mps

The main turrets of German capital ships were – with a few exceptions – hydraulically trained, the system being powered by electrically-driven pumps. The complete loading procedure was governed by the Siemens-designed remote power control (RPC) apparatus, based on a tacho-generator/thyratron operating the four main valves, which was fitted to all turrets with guns of 203mm calibre and above. However, its performance was considered far from satisfactory, control being non-linear and depending on acceleration and on the pressure-drop in the accumulator, and attempts to improve it were largely unsuccessful. A new system designed by Askania and fitted in the

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THE 38cm SK C/34 GUN OF THE BATTLESHIPS BISMARCK AND TIRPITZ

Above: The battleship Bayern, whose main armament was the starting-point for that of Bismarck and Tirpitz. (A Jarski collection)

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Above: Forward turrets of the Bismarck during final fitting-out in the spring of 1940. Note that the armoured rangefinder covers on ‘A’ turret are still empty. (Blohm & Voss via Jörg Schmiedeskamp)

Below: Bismarck steaming along the River Elbe, towards the Kiel Canal, on 15 September 1940. Note that ‘A’ turret still has its 10m optical rangefinder, which was later removed. (S Breyer collection)

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HEAVY GUNS

Above: The crew of the Deutschland off duty during their first deployment to Spanish waters, between 26 July and 25 August 1936. On 31 July Deutschland was ordered to paint the national colours on top of the main turrets for better identification by friendly air forces. These were painted across the front top slopes.

(M Krzy˙zan collection) Left: Deutschland’s ‘A’ turret. The roof and top slopes were painted dark grey as an identification sign for the Luftwaffe.

(CAW collection)

Opposite: Deutschland’s ‘A’ turret painted light grey. It was painted this colour in April 1934, during Hitler’s visit. This photo shows her steaming across the Songe fjord. (CAW collection)

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THE 28cm SK C/28 GUNS OF THE DEUTSCHLAND CLASS ‘POCKET BATTLESHIPS’

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Above: Deutschland moored at the Gazelebrücke. Coffins with fallen sailors are laid at the foot of ‘B’ turret, awaiting transfer to the trucks waiting on the quay.

This shot shows many details of ‘B’ turret, which bore the name ‘Hindenburg’ as well as the Hindenburg family’s coat of arms on the sides. (CAW collection)

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GERMAN NAVAL GUNS 1939-1945

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Bismarck’s searchlight platform also held two 2cm Flakvierling 38 quadruple anti-aircraft guns, again the land model, placed on either side of the foremast, above the admiral’s bridge.

Tirpitz also received the new quadruple anti-aircraft mounts, the 2cm Flakvierling 38s. Eight of these were mounted between March and June 1942, and more were added later.

Minor additions to Tirpitz’s armament were introduced during the winter of 1943/44, when she returned to active service.

Systematic air raids against the battleship made augmenting the anti-aircraft defenses necessary.

To bolster the defenses ten more 20mm guns were installed, including two quadruple Flakvierling 38s.

In April–May 1944, four more Flakvierling 38 mounts were fitted to Tirpitz’s main deck.

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GERMAN NAVAL GUNS 1939-1945

Deutschland’s ‘A’ turret shortly after commissioning, with no nameplates etc.

Later on ‘A’ turret was christened ‘Hitler’, and had NSDAP emblems and nameplates affixed on either side.

Deutschland’s ‘B’ turret aft was identical – except for emblems and markings.

Deutschland’s ‘B’ turret was christened ‘Hindenburg’, and had the Hindenburg family coat of arms at the sides.

Admiral Graf Spee’s ‘A’ turret was named ‘SMS Scharnhorst’ and wore this warship’s coat of arms on the sides.

Admiral Scheer’s ‘A’ turret was marked with the Lützow family crest.

Deutschland’s ‘A’ turret during the early part of her career. The white circle on a red background painted on the roof of the turret was a recognition sign for the Luftwaffe.

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MEDIUM GUNS

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15cm Tbts K C/36 gun in Tbts L C/36 mount

Tube with breech – side view (cross-section).

Tube with breech – top view.

Tube with breech and cradle – side view.

Top view.

View and section of the pedestal and lower mount.

Cradle.

Front view.

Arresting gear (turnbuckles).

Side view.

Rear view.

Angles of elevation.

Top view.

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THE 15cm TBTS K C/36 GUN ABOARD DESTROYERS

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solenoid, the 1kW permanent and 3kW peak output training and elevating motors and the portable auxiliary lighting for the mount. A 4V transformer also powered lights for the sights, the control positions and the breech, as well as the firing warning system (blue and red lights and a buzzer).

The DrhL C/38 twin turret The DrhL C/38 was originally designed for Battlecruisers ‘O’, ‘P’ and ‘Q’ and the scout cruisers, but when these were cancelled it was decided to arm the modernised 1934A class destroyers with them.

Stability problems had handicapped these ships by forcing the reduction of their 150mm battery from five single mounts to four, and it was hoped that mounting the twin turret in place of the forward single mount would restore the fifth gun without causing the same stability problems.

Two 15cm Tbts K C/36 guns were therefore fitted in a new ‘lightweight gun turret’, in which extensive use of welding and other modifications were expected to result in considerable weight savings. However, despite all this, the turret still weighed almost twice as much as the single mount it was to replace. There were also problems integrating the new twin turret into the ships’ existing fire-control systems. Future destroyer classes were planned to mount two of these turrets, but nothing came of this before the end of the war.

Above: One of only a few photos which show brass nameplates on individual gun houses.

(CAW collection) Above, left: A destroyer’s stern – in the foreground no. 3 gun barrel.

(CAW collection)

Left: Destroyer armed with 127mm guns steams by one of her sister-ships.

Later on this armament was replaced by 150mm guns.

(CAW collection)