Planned for the never-built B-65 class "Super A" cruisers, it appears that no prototypes were ever started. Information on these weapons is based entirely upon the B-65 preliminary design, completed in September 1940. The ships were postponed on 6 November 1941 and officially cancelled following the Battle of Midway in June 1942.
Type 0 (Model 1940) is my estimate, but they may have been designated as Type 94 (Model 1934) if their breech mechanism design followed that of the 46 cm guns used on the Yamato class.
Nomenclature note: "Japanese Cruisers of the Pacific War" states that: "Some sources mention 30 cm, but the actual caliber was to have been 310 mm." This reference further states that 12" (30.5 cm) is "used in non-Japanese publications and non-official Japanese works."
|Designation||31 cm/50 (12.2") Type 0 (?) (Model 1940)|
|Ship Class Used On||B-65 class (Warships #795 and 796)|
|Date Of Design||about 1940|
|Date In Service||N/A|
|Gun Length oa||N/A|
|Bore Length||about 610.2 in (15.500 m)|
|Rate Of Fire||about 3 rounds per minute|
|Projectile Types and Weights||AP - 1,265 lbs. (561 kg)|
|Approximate Barrel Life||N/A|
|Ammunition stowage per gun||N/A|
|45 degrees||36,000 yards (32,920 m)|
|Elevation||-5 / +45 degrees|
|Train||About +150 / -150 degrees|
"Naval Weapons of World War Two" by John Campbell
"Japanese Cruisers of the Pacific War" by Eric Lacroix and Linton Wells II
"Battleships; Axis and Neutral Battleships in World War II" by W.H. Garzke, Jr. and R.O. Dulin, Jr.
09 October 2006 - Benchmark
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