The 5"/54 (12.7 cm) Mark 16 was originally planned for the never-built Montana Class battleships, but they made their first service debut on the Midway Class Large Aircraft Carriers. Essentially, this weapon was simply a longer version of the previous 5"/38 (12.7 cm) Mark 12 and should not be confused with later 5"/54 (12.7 cm) weapons which included automatic ammunition feeding provisions. This gun was not as popular as the 5"/38 Mark 12, possibly because the larger projectile and cartridge cases resulted in faster crew fatigue.
These guns were gradually removed from the Midway class carriers as weight compensation for growth in other areas. Some of these mountings were then reused on new-construction Japanese destroyers.
At least two mountings still exist, one at the Military Museum of Southern New England in Danbury, Connecticut and the other at the White Sands Missile Range in New Mexico.
Nomenclature Note: This was the last USN 5" (12.7 cm) gun that was known by the gun barrel Mark number designation. All subsequent 5" (12.7 cm) guns are known by the mounting Mark number designation.
Designation 5"/54 (12.7 cm) Mark 16
Ship Class Used On
(see Note) Planned for Montana BB-67 Class
Midway CVB-41 Class
Japanese Akizuki (DD-161 ex-USS DD-961) and Murasme (DD-107) classes
Date Of Design 1939
Date In Service 1945
Gun Weight 5,361 lbs. (2,432 kg) (without breech)
Gun Length oa N/A
Barrel and Bore Length 270.0 in (6.858 m)
Rifling Length 229.07 in (5.820 m)
Grooves N/A
Lands N/A
Twist Uniform RH 1 in 25
Length Of Rifling 229.07 in (5.820 m)
Chamber Volume 825.38 in3 (13.525 dm3)
Rate Of Fire 15 - 18 rounds per minute
Elevation With 70 lbs. (31.75 kg) HCC Shell
Range @ 10 degrees 13,000 yards (11,887 m)
Range @ 15 degrees 16,300 yards (14,905 m)
Range @ 20 degrees 19,000 yards (17,374 m)
Range @ 30 degrees 22,500 yards (20,574 m)
Range @ 35 degrees 24,100 yards (22,860 m)
Range @ 45 degrees 25,909 yards (23,691 m)
AA Ceiling @ 85 degrees 51,600 feet (15,728 m)
Designation Single Mount
Midway (18), Akizuki (3) and Murasme (3): Mark 39
Twin Mount
Montana (10): Mark 41
Weight Mark 39: 33 tons (33.5 mt)
Mark 41: N/A
Elevation -10 / +85 degrees
Rate of Elevation 15 degrees per second
Train about -150 / +150 degrees
Rate of Train 30 degrees per second
Gun Recoil 19 in (48.3 cm)
Notes:
1) USS Coral Sea (CVB-43) had only 14 single mounts when commissioned. The Midway class carriers had the number of guns reduced over the years as compensation for weight growth in other areas, with all guns removed from Midway and Coral Sea by 1980 (the third member of the class, USS Franklin D. Roosevelt CV-42, was retired in 1977).
2) Both the single and the twin mountings were base ring types and had projectile and powder hoists on the axis of the mount.
3) A minimum crew of sixteen men were required for the single mounting, with ten in the gun room and six in the handling room.
4) These mountings used amplidyne all-electric power drives.
Here is a proposed 5/54 Mk16 data, max vertical range is reduced simply because fusing would have exploded the shell way before it reached its zenith:
