Imperial Japanese Navy Ammunition - 127mm Projectiles

Imperial Japanese Navy Ammunition

 

12.7cm (127mm)(5-inch) Complete Round (Fixed)

  

 

Case:

-Length: 22.88 inches

-Diameter of base: 6.66 inches

-Material: Brass

-Weight (empty): 16.28 lbs

 

The case is crimped tightly into a groove in the base of the projetile by a single continuous crimp.

 

Propellant:  21 DC (Type 13 propellant): 8.87 lbs

 

Unperforated cylindrical sticks approximately 2.1mm by 15.75 in, graphited double-base powder.  The propellant sticks are enclosed in a compartmented bag of heavy brownish silk.

 

Primer: Mk 2 case percussion primer Model 4

 

Weapons used in:

-Type 88 12.7cm/40 dual-purpose gun

-Type 89 12.7cm/40 dual-purpose gun (twin)

 

This latter is a modern gun, paired in a twin power-driven mount designed especially for anti-aircraft aboard ships.  It has been found ashore, unaltered, in the characteristic gun-house mount used aboard ship.

 

Special features of this gun and mount are horizontal opposed sliding breech blocks, full power drive, and automatic fuze-setting accomplished as the loading tray moves the round into position to be rammed.  The arrangement for loading and fuze-setting and the general plan of the mount corresponds closely to that of the Type 98 10cm/65 twin mount.

 

 

 

 

 

12.7cm (127mm)(5-inch) High-Explosive

 

 

Assembled round:

-Weight of complete round: 73.57 lbs

-Length of complete round (with Type 91 fuze): 36 inches (approx)

 

Projectile:

-Weight of filled projectile (without fuze): 48.42 lbs

-Weight of empty projectile: 44.48 lbs

-Weight stamped on rotating band (sample): 20.17kg (varies with individual projectiles)

 

Dimensions:

-Length of projectile (without fuze): 14.9 inches

-Diameter at bourrelet: 4.96 inches

-Distance from base to rotating band: 1.19 inches

-Width of rotating band: 1.95 inches

-Radius of ogive: 6 cal.

 

Filling:

-Cast picric acid (shimose): 3.94 lbs

 

The charge consists of a single block of explosive cast and sealed in a waxed-paper container, encased in a heavy cotton-flannel bag and sealed in the projectile with paraffin.

 

Fuzing:

-Type 91 mechanical time fuze

-Type 88 point detonating fuze

 

Weapons used in:

-Type 89 12.7cm/40 dual-purpose gun

-Type 88 12.7cm/40 dual-purpose gun

 

 

 

  

(Type 3 Ordinary) 12.7cm (127mm)(5-inch) Incendiary Shrapnel

   

 

Assembled round:

-Weight of complete round: 78.36 lbs

-Length of complete round (without fuze): 36.43 inches

 

Projectile:

-Weight of filled projectile (without fuze): 53.21 lbs

-Weight of empty projectile: No Data

-Weight stamped on rotating band (sample): 17.17 kg (varies with individual projectiles)

 

Dimensions:

-Length of projectile (without fuze): 14.8 inches

-Diameter at bourrelet: 4.97 inches

-Distance from base to rotating band: 1.25 inches

-Width of rotating band: 2 inches

-Radius of ogive: 6 cal

 

Filling:

-Cast picric acid (shimose): 162 grams

-Tetryl: 2.3 grams

-Lead Azide: 0.13 grams

-Black powder: 35 grams

 

Incendiary charge (43 steel pellets 50mm in length and 20mm in diameter filled with a dry incendiary mix of the following composition):

-Magnesium: 54 percent

-Barium dioxide: 26 percent

-Rubber: 15 percent

-Iron oxide: 1.5 percent

-Sulphur: 3 percent

 

Fuzing: Type 91 mechanical time fuze

 

Weapons used in:

-Type 89 12.7cm/40 high-angle gun.

 

Remarks:

The black powder charge in the nose ignites the incendiary pellets and flashes down the central tube igniting relay disks and the expelling charge.

 

The expelling charge ejects the incendiary pellets and ignites a primer in the base section which detonates the gaine and bursting charge.

 

 

 

 

12.7cm (127mm)(5-inch) Practice

 

 

Assembled round:

-Weight of complete round: 75.84 lbs

-Length of complete round: 40.2 lbs

 

Projectile:

-Weight of filled projectile: 50.69 lbs

-Weight of empty projectile: 48.10 lbs

-Weight stamped on rotating band (sample): 21.8 kg (varies with individual projectiles)

 

Dimensions:

-Length of projectile: 17.31 inches

-Diameter at bourrelet: 4.97 inches

-Distance from base to rotating band: 1.61 inches

-Width of rotating band: 1.95 inches

-Radius of ogive: 6 cal

 

Filling: Sand

 

Fuzing: None

 

Weapons used in:

-Type 89 12.7cm/40 dual-purpose gun

 

 

 

 

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