28 cm SK C/34 naval gun

The German 28 cm SK C/34^{[Note 1]} naval gun was a 283 mm 54.5-caliber built-up gun designed in 1934 used on the Scharnhorst-class battleships.

Gun from Gneisenau being unloaded in Bergen, Norway, prior to installation at Fjell festning, late 1942-early 1943
Type	Naval gun Coast-defense gun
Place of origin	Germany
Service history
In service	1938–1953
Wars	World War II
Production history
Designed	1934
Specifications
Mass	53,250 kg (117,400 lb)
Length	15.4 m (51 ft) 54.5 Caliber
Barrel length	14.5 m (48 ft) (bore length)
Shell	Separate-loading, bagged charge
Caliber	283 mm (11.1 in)
Elevation	–8° to +40°
Muzzle velocity	890 m/s (2,900 ft/s)
Maximum firing range	40,930 m (44,760 yd) at 40°[1]

History

The previous 28 cm gun was the SK C/28 used on the Deutschland class. The Scharnhorst class received an improved version of the SK C/28 which had a longer barrel—the SK C/34.

The 283 mm SK C/34 gun was relatively fast loading, compared with other armament of this size. It could deliver a shot every 17 seconds. The ballistic properties of the guns made them effective against the new French Dunkerque class, which had an armored belt 225–283 mm, barbettes of 310–340 mm, at standard fighting distances.

An improved version of the gun was planned to be mounted on the Netherlands' Design 1047 battlecruisers, but the ships were never begun due to the start of the Second World War.^[2]

When Gneisenau's turrets were removed for re-arming and upgunning to 38 cm in 1942–43, her guns were redeployed for coast defence at Fjell festning ´(11.MAA 504) in Sotra, Norway (Bruno turret), at Batterie Oerlandat (4.MAA 507) in Austrått, Norway (Cesar turret), and guns from Anton turret were installed at Battery Rozenburg in the Netherlands.^[3]

One of Gneisenau's turrets and its guns were also considered for the hypothetical Landkreuzer P. 1000 Ratte super-heavy tank.

Characteristics

Effectiveness of the guns against armor in different situations^{[citation needed]}

Distance	0	7,900 m (8,600 yd)	15,100 m (16,500 yd)	18,288 m (20,000 yd)	27,432 m (30,000 yd)
Shooting angle[deg]	0	3.3	7.4	9.7	18.7
Shell hitting angle[deg]	0	4.4	10.3	15.2	30.2
Shell velocity at target	890 m/s (2,900 ft/s)	693 m/s (2,270 ft/s)	552 m/s (1,810 ft/s)	496 m/s (1,630 ft/s)	420 m/s (1,400 ft/s)
Side armor belt penetration	604 mm (23.8 in)	460 mm (18 in)	335 mm (13.2 in)	291 mm (11.5 in)	205 mm (8.1 in)
Deck armor penetration	-	19 mm (0.75 in)	41 mm (1.6 in)	48 mm (1.9 in)	76 mm (3.0 in)

Ammunition

Coast-defence shell at Fjell festning in Sotra, Norway

Characteristics of SK C/28 and SK C/34 283 mm shells:

Gun type	Shell type	Length (calibers)	Total weight
SK C/28	Armor-piercing	3.7	300 kg (660 lb)
	Semi-armor-piercing	4.2	300 kg (660 lb)
	Igniting	4.2	300 kg (660 lb)
SK C/34	Armor-piercing	4.4	336 kg (741 lb)
	Semi-armorpiercing	4.4	316 kg (697 lb)
	Igniting	4.5	315 kg (694 lb)

Surviving examples

Gneisenau's Cäsar turret at Austrått fort, Ørlandet, Norway

• Gneisenau's Cäsar turret with its 3 guns survives at Austrått fort, Ørlandet, Norway
• Parts of the guns from Anton turret survive at former "Stichting Fort", Hook of Holland

See also

• List of naval guns