United States of America
5"/54 (12.7 cm) Mark 16
Updated 22 November 2014

This weapon grew out of a design study for replacing the 5"/38 (12.7 cm) Mark 12 and was originally planned for the never-built Montana Class battleships.  They actually made their first service debut aboard the large aircraft carriers of the Midway class (CVB-41) and later on the gunnery training ship USS Mississippi AG-128 (ex BB-41).

This gun was not as popular as the 5"/38 (12.7 cm) Mark 12, possibly because the larger projectile and cartridge cases resulted in faster crew fatigue.  Essentially, this weapon was simply a longer version of the 5"/38 (12.7 cm) Mark 12 and should not be confused with the later 5"/54 (12.7 cm) weapons which included automatic ammunition feeding provisions.

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) weapon that was best known by the gun barrel Mark number designation although a few documents refer to it per its Mark 39 mounting designation.  All subsequent 5" (12.7 cm) designs are known by the mounting Mark number designation.


USS Midway CVB-41 as completed in September 1945 with eighteen 5"/54 (12.7 cm) guns
These carriers had improved flight deck operation as compared to the Essex class as all their 5" (12.7 cm) AA guns were mounted below the flight deck level
U.S. Naval Historical Center Photograph # 97631

Click here for additional pictures
Gun Characteristics
Designation 5"/54 (12.7 cm) Mark 16
Ship Class Used On
(see Note)
   Planned for Montana (BB-67) Class
   Midway (CVB-41) Class
   Mississippi (AG-128)

   Akizuki (DD-161, ex-USS DD-961) and Murasme (DD-107) classes

Date Of Design 1940
Date In Service USN:  1945
Japan:  1960
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
Note:  Akizuki and her sister Teruzuki were laid down by Mitsubishi in 1959 to a modified USS Fletcher (DD-445) design.
Type Separate
Projectile Types and Weights
(see Note 1)
HC Mark 41 Mod 0 with PD fuze - 69.33 lbs. (31.448 kg)
HC Mark 41 Mod 0 with MT fuze - 69.45 lbs. (31.505 kg)
HC Mark 41 Mod 0 with VT fuze - 69.19 lbs. (31.384 kg)
SP Common Mark 42 Mods 0 and 1 - 70.0 lbs. (31.75 kg)
Illum Mark 33 Mod 0 - 70.0 lbs. (31.75 kg)
Illum Mark 48 Mod 0 - 69.2 lbs. (31.39 kg)
Bursting Charge HC Mark 41 - 7.75 lbs. (3.515 kg) Explosive D
SP Common Mark 42 Mods 0 and 1 - 2.14 lbs. (0.97 kg) Explosive D
Projectile Length 26.0 in (66 cm)
Cartridge Case Type, Size and Empty Weight Mark 6 - Brass, 127 x 836 mm, 13.04 lbs. (5.91 kg)
Propellant Charge 18.5 lbs. (8.19 kg) SPD or SPDN
Flashless - 19.0 lbs. (8.62 kg) SPDF
Muzzle Velocity 2,650 fps (808 mps)
Working Pressure 18.5 tons/in2 (29,137 kg/cm2)
Approximate Barrel Life 3,070 Rounds
Ammunition stowage per gun Midway and Montana:  about 500 rounds
Akizuki:  330 rounds

1) Special Common Mark 42 had a windscreen and a thin hood and was strengthened to enhance its armor piercing qualities.  Mark 41 projectile bodies could be used with Point Detonating (PD), Mechanical Time (MT) or with proximity (VT) nose fuzes.  When used with PD fuzes, they were considered to be HC rounds while those with MT and VT fuzes were considered as AA rounds.  Rounds with MT or PD nose fuzes had an instantaneous contact type base fuze.  A blind plug was used in place of the base fuze for those projectiles using VT nose fuzes.

2) The illumination round burns for approximately 50 seconds.

3) Bourrelet diameter was 4.985 inches (12.66 cm).

4) The wide availability of ammunition for this and subsequent USN 5"/54 (12.7 cm) guns led the French to use these munitions for their own 127 mm (5") guns.

Elevation With 70 lbs. (31.75 kg) HC 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)

Mount/Turret Data
(see Note 1)
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)

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 single and 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.  Additional crewmen were required in the lower ammunition spaces.

4) These mountings used amplidyne all-electric power drives.

Data from
"Jane's Pocket Book 9:  Naval Armament" edited by Denis Archer
"Naval Weapons of World War Two" by John Campbell
"US Battleships:  An Illustrated Design History," "US Carriers:  An Illustrated Design History," "US Naval Weapons" and "The Naval Institute Guide to World Naval Weapon Systems 1991/92" all by Norman Friedman
"Battleships:  United States Battleships, 1935-1992" by W.H. Garzke, Jr. and R.O. Dulin, Jr.
"Illustrated Complete Ship's Data JMSDF 1952-98" by Ishibashi Takao
"Naval News in Pictures" Warship International No. 2, 1987
"Naval Ordnance and Gunnery - 1952" Navpers 16116-B
"U.S. Explosive Ordnance:  Ordnance Pamphlet 1664 - May 1947" by Department of the Navy
White Sands Missile Range Press Releases
Special help by Leo Fischer
Page History

12 August 2008 - Benchmark
23 March 2012 - Added source for picture page
16 April 2013 - Added link to French 127 mm datapage
22 November 2014 - Added note about Mark 39 designation