Published on
January 18, 2010 in
Japanese.
This grenade, designed to be fired from Models 38 and 99 rifles by means of a spigot launcher and wooden bullet, is similar in use and operation to the Model 91 rifle grenade. However, it is smaller and has a smooth-wall body rather than the serrated type. It contains a cyclonite primer enclosed in a brass container, a tetryl booster, and a three-ounce bursting charge of cast TNT; it is also fitted with an instantaneous fuze and a tail assembly with four fins spot welded to the rear part of the tube.
The grenade is armed by the removal of a safety fork. On impact, an inertia block is forced into the fuze body shearing a brass shear wire and driving the firing pin into the detonator.
SPECIFICATIONS
| Diameter of grenade body | |
1.63 ins. |
| Length of grenade body | |
2.43 ins. |
| Wall thickness | |
1/8 in. |
| Overall length of grenade | |
7.88 ins. |
| Weight of grenade without explosive | |
14 ozs. |
| Weight of explosive body without explosive | |
10 ozs. |
| Length of fin assembly | |
4 15/16 ins. |
| Outside diameter of tube | |
1 13/16 ins. |
| Inside diameter of tube | |
1 1/16 ins. |
| Width of tail assembly | |
2 1/8 ins. |
| Length of tail fin | |
2 3/8 ins. |
| Width of tail fin | |
1/4 in. |
| Material of construction | |
Steel |
| Weight of main charge | |
3 ozs. |
| Weight of primer | |
3 gr. |
| Weight of booster | |
1 gr. |
Japanese: p. 304.2 (April 1, 1945)
Published on
January 16, 2010 in
Japanese.
It is believed that this naval coast defense weapon was designed primarily for use against ships, as the fuzes used with the gun’s ammunition are not sensitive enough to function satisfactorily upon impact with soft ground. This gun uses separate loading ammunition, and has a standard type mushroom head obturator. The breechblock is the horizontal swinging, interrupted screw type, having three threaded segments with two step threads. A hydropneumatic recoil mechanism is located above the barrel.
A naval pedestal type mount is used. Strips of iron fastened to and radiating from the pedestal are buried in the ground to insure stability. The piece is sometimes fitted in a casemate, the front and sides of which are cast in one piece. The top is rolled plate. A mantlet is fitted to the gun on the inside of the casemate. Gun and casemate are rotated manually, as no power system is provided.
No fire control equipment, with the exception of a telescopic sight mount, was recovered with the gun, and it is believed that the piece is fired by direct laying.
SPECIFICATIONS
| Caliber |
|
140 mm (5.5 ins.) |
| Weight (firing position) |
| Length (overall) |
|
23 ft., 8 ins. |
| Length (firing position) |
| Height (firing position) |
| Width (overall) |
| Length of tube |
|
22 ft., 10 1/2 ins. |
| Length of rifling |
|
19 ft., 3 1/2 ins. |
| No. of grooves |
|
42 |
| Width of grooves |
| Depth of grooves |
|
0.051 in. |
| Width of lands |
| Muzzle velocity (shell) |
|
850 meters (2,789 ft.) per sec.
from range disc on gun |
| Max. range (horizontal) |
|
17,000 meters (18,598 yds.)
from range disc on gun |
| Rate of fire |
| Traverse |
|
360° |
| Elevation |
|
30° |
| Depression |
|
-7° |
| Length of recoil |
| Ammunition |
| Wt. of projectile (H.E.) Common |
|
83.8 lbs. |
Japanese: p. 114.6 (August 1, 1945)
