Description

This was to be Germany's first DP destroyer gun. However, the two ships intended to carry these guns, Z46 and Z47, were both severely damaged while under construction in 1944 and never completed.

This gun fired fired very streamlined projectiles, some of which had ballistic caps as much as 20crh. It is sometimes confused with the well-known 12.8 cm Flak 40 which was used to protect German cities but which was never mounted afloat.

Construction details are not known, but it is possible that these weapons would have had similar features as other late-war German guns, such as a three-piece barrel.

Nomenclature note: This gun was possibly also known as the "12.8 cm SK C/41" gun.

Gun Characteristics

Designation 12.8 cm/45 (5") KM411
Ship Class Used On Planned for Z46 and later classes
(Types 36C, 41, 42C and "Zerstörer 1945")
Date Of Design 1941
Date In Service N/A
Gun Weight 4.18 tons (4,250 kg)
Gun Length oa 228.6 in (5.807 m)
Bore Length 212.6 in (5.400 m)
Rifling Length 178.6 in (4.547 m)
Grooves (40) 0.067 in deep x 0.199 in (1.7 mm x 5.05 mm)
Lands 0.197 in (5.0 mm)
Twist Increasing RH 1 in 35.9 to 1 29.9
Chamber Volume 877 in3 (14.37 dm3)
Rate Of Fire 15 - 18 rounds per minute
  • ^"German Destroyers of World War Two" by M.J. Whitley refers to this gun as the "12.8 cm SK C/41".

Ammunition

Type Fixed
Weight of Complete Round 108 lbs. (49 kg)
Projectile Types and Weights HE: 61.7 lbs. (28 kg)
Bursting Charge N/A
Projectile Length N/A
Complete round was 53.0 in (134.6 cm)
Propellant Charge 22 lbs. (10 kg) RPC/40N (6.5/2.5)
Muzzle Velocity 2,723 fps (830 mps)
Working Pressure 18.7 tons/in2 (2,950 kg/cm2)
Approximate Barrel Life N/A
Ammunition stowage per gun Type 36C: 120 rounds
Type 41, 42C and Z1945: 180 rounds

Range

Range with 61.7 lbs. (28 kg) HE
Elevation Distance
40 degrees 24,060 yards (22,000 m)
70 degrees about 40,000 feet (12,200 m)

Mount / Turret Data

Designation Twin Mounts
    Type 36C (3), Type 41 (2), Type 42C (3), "Z1945" (4): Drh LC/41
Weight 89,290 lbs. (40,500 kg)
Elevation -10 / +60 degrees 1a
Elevation Rate N/A
Train -170 / +170 degrees
Train Rate N/A
Gun recoil N/A
  • ^"Naval Weapons of World War Two" says -15 / +52 degrees.

Sources

Naval Weapons of World War Two" by John Campbell
"German Warships 1815-1945" by Erich Gröner
"German Destroyers of World War Two (2nd Edition)" by M.J. Whitley
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Special help from Thorsten Wahl

Page History

09 May 2006 - Benchmark
01 April 2012 - Updated to latest template
30 January 2019 - Converted to HTML 5 format
09 November 2022 - Added sketch of Fire Control System
22 August 2024 - Minor changes