Tag: artillery

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Japanese

40 cm Base Range Finder

40 cm Base Range Finder - WWII, Japanese

This range finder is a superimposed image vertical base instrument designed for use with machine gun and mortar fire. It consists of two major assemblies: the elbow, and the diaspirometer unit and head. The elbow housing is of seamless aluminum, 4 3/4 inches in length. It contains the eye and field lens, an amici prism, a reticle, a penta prism, and the objective lens. The brass diaspirometer unit contains two wedges with connecting gears that govern the aluminum range drum; the extension tube made of seamless aluminum which maintains the base length of the instrument; and the cast aluminum head which houses a penta prism and a weak correction wedge.

The instrument is used in conjunction with a mount and tripod. Because of the short base length, this range finder is not accurate at distant ranges.

SPECIFICATIONS

Power           4 diameters
Field of view (upper field) 11°
      (lower field) 4°
Base length 40 cm
Measuring limits 30 to 1,500 meters

Japanese: p. 179 (March 1, 1945)

Categories
Japanese

150 mm Mortar, Model 97 (1937)

150 mm Mortar, Type 97 (1937)

This mortar, of conventional design, is a smooth bore, muzzle-loading weapon referred to by the Japanese as a medium mortar. Although its tactical use is not fully defined, it is known to have been used in fixed concrete emplacements as a part of the island defense system.

The Model 97 is very heavy and sturdily constructed, weighing 770 pounds complete with sight. The breech cap and stud, with assembled firing mechanism, are screwed on in the normal manner. The firing pin may be adjusted to three different positions by means of a cam lock. When the lock is in the rear center position the firing pin is in a safe position; when the lock is turned to the right, the pin is “Floating,” or, in other words, may be actuated by a sharp blow on the end of the cam shaft. When the firing pin is locked forward, the operation is the same as that of a mortar with a fixed firing pin.

The bipod is of normal construction with but one exception. The elevating screw is actually two concentric screws, comparing very favorably with a single screw in stability and overall length. The traversing screw, buffer mechanism, and collar assembly are of the same design as other Model 97 Japanese mortars. The bipod and cradle may be separated for handling.

The base plate is a heavy ribbed stamping of 0.25 inch metal built up by reinforcing ribs welded to the original stamping. It has the usual ball and socket locking arrangement. The sight is a panoramic elbow telescope of three power and thirteen degree field.

SPECIFICATIONS

Caliber         150 mm (5.906 ins.)
Weight (complete) 770 lbs.
Weight of tube 257 lbs.
Weight of bipod & traversing assembly (total) 174.5 lbs.
Weight of sight & extension 1.5 lb.
Weight of baseplate 337 lbs.
Length of tube 75.37 ins.
Length of tube (internal) 66 ins.
Length of baseplate 47.75 ins.
Width of baseplate 35.5 ins.

Japanese: p. 127 (March 1, 1945)

Categories
Japanese

140 mm Seacoast Gun Type 3

140 mm Seacoast Gun Type 3 -- Japanese, WWII

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)

Categories
Japanese

120 mm, 45 Caliber, Naval Dual Purpose Gun, Type 10

120 mm, 45 Caliber, Naval Dual Purpose Gun, Type 10 (Japanese WWII)

The Japanese Type 10 dual purpose gun has a 45-caliber barrel of monobloc construction with uniform right hand rifling. A long, narrow rectangular projection on the bottom of the barrel slides in a groove in the sleeve type cradle, preventing the barrel from rotating. The bearing surface for recoil being the machined barrel surface. The cradle is mounted on a pedestal mount which permits a traverse of 360 degrees.

The elevating handwheel is on the right side of the mount, while the traversing handwheel is on the left. An auxiliary handwheel on the left side permits the piece to be elevated and traversed by the gunner. To compensate for muzzle preponderance, a spring pusher type equilibrator is used. The gun is well balanced, and exceptionally easy to elevate. The recoil mechanism is a hydrospring type, the two outside cylinders housing the counterrecoil springs, and the center cylinder the hydraulic mechanism. A semiautomatic horizontal sliding breechblock is used.

The mount is of riveted construction.

SPECIFICATIONS

Caliber       120 mm (4.7 ins.)
Weight (firing position) 6,500 lbs.
Length (gun and mount) 19 ft., 6 1/2 ins.
Length (firing position)
Height (gun and mount) 7 ft., 8 1/2 ins.
Height (firing position)
Width (gun and mount) 7 ft., 1 in.
Length of tube 17 ft., 1 1/2 ins.
Length of rifling 14 ft., 9 1/2 ins.
Length, of chamber 29.5 ins.
No. of lands 34
Width of grooves 1/4 in.
De-th of grooves .050 in.
Width of lands 1/8 in.
Muzzle velocity (shell) 2,700 f/s
Max. range (horizontal) 17,000 yds.
Max. range (vertical) 32,800 ft. (fuze)
Rate of fire 10-12 rds.
Traverse 360°
Elevation 75°
Depression 10°
Length of recoil 19.3 ins.
Ammunition H.E. shrapnel; H.E. phosphorus
Wt. of projectile 45.75 lbs.

Japanese: p. 114.5 (August 1, 1945)

Categories
Japanese

120 mm, 45 Caliber, 11 Year Type Gun

Japanese 120mm 45 Caliber 11 Year Type Gun

This gun is a naval coast defense weapon manufactured at Sasebo Arsenal. It uses semi-fixed ammunition. The barrel is of built-up construction with uniform right hand twist rifling. A manually operated, horizontal sliding block breech mechanism is used. It is unusual in that the block does not pass all the way across the rectangular breech ring. The rear of the breech ring is cut in a keyhole shape. The operator of the elevation handwheel may fire the gun by means of a lever mechanism, or it may be fired by a lanyard attached to the right side of the breechblock.

The recoil system comprises three cylinders, two located above and one below the barrel.

The mount consists of a rectangular upper carriage which is mounted on a pedestal normally embedded in a solid foundation. A traversing scale is located on the pedestal. The traversing handwheel is in a horizontal position with the vertical shaft engaging a series of gears in the base mount. Platforms attached to the upper pedestal are provided for the gun layers and move in traverse with the gun.

Fire control equipment is of the usual Japanese naval coast defense gun type.

SPECIFICATIONS

Caliber      120 mm (4.72 ins.)
Weight (traveling position)
Weight (firing position)
Length of gun (overall)18 ft., 3 1/4 ins.
Length of tube 17 ft., 3 3/4 ins.
Height of gun 6 ft., 11 ins.
Height (firing position)
Width (overall)
Length of rifling 14 ft., 8 1/2 ins.
No. of lands34
Width of grooves
Depth of grooves
Width of lands
Muzzle velocity (H.E. shell)2,700 f/s
Max. range (horizontal)
Max. range (vertical)
Rate of fire
Traverse360°
Elevation50°
Depression10°
Length of recoil
AmmunitionH.E.
Wt. of projectile (H.E.)44.75 lbs.

Japanese: p. 114.4 (August 1, 1945)

Categories
German

17 cm Steel Cartridge Case, Spiral Design

17 cm Steel Cartridge Case, Spiral Design

This is a large caliber steel cartridge case of different design from those customarily used by the Germans. The body is a wound cylinder made of 0.084 inch thick sheet steel three and four turns thick and turned under at the base to fit into a base assembly. The base assembly is provided with a retaining plate, screwed collar, and a disc which seals the cartridge case and prevents the escape of gases through the base. The disc is of cardboard; all the other parts are of steel.

A shallow spiral groove, about 0.003 inch deep and .23 inch wide, is rolled into the inner surface of the body under such pressure as to show the marks of the groove on the outer surface of the case. A layer of black wax is used between the overlapping coils of the body to assist waterproofing. The upper surface of the cardboard disc is also covered with black wax. It appears that this case is manufactured by coiling the sheet approximately to shape, placing the body in a die and rolling to shape with an internal roller. The base, retaining plate, and screwed collar have completely machined surfaces. All the parts have a thin surface film of oxide for protection from corrosion. This is not completely effective.

The Vickers Diamond Hardness of the body increases from about 105 near the base to 133 near the mouth. It is approximately 222 across the base except in the primer boss where it is about 280. On the retaining plate the V. D. H. varies from 160 at the center to 172 on the rim. The screwed collar is 175 V. D. H.

German: p. 314

Categories
German

28 cm R. Gr. 4331: Rocket Assisted Prerifled Projectile

28 cm R. Gr. 4331: Rocket Assisted Prerifled Projectile

This high explosive projectile is fired from the 28 cm K. 5 (E) railway gun, and is prerifled in the same manner as the 28 cm Gr. 35 described on page 312. The outstanding feature of this new projectile is an increase in range from 67,800 yards to 93,100 yards—nearly 53 miles. This increase of 37% over the maximum range for the standard high explosive round is the result of energy supplied to the projectile by the addition of rocket propellant powder which is ignited 19 seconds after leaving the gun. After building up sufficient pressure to shear the lip on the base plug, the rocket propellant located in the ogive of the projectile discharges through a central venturi tube.

On the main body there are 12 steel splines set at the angle of rifling. The forward body (ogive) is threaded externally to screw into the main body and internally at its nose to receive the fuze and a rocket propellant ignition system. The venturi tube which extends from the base of the projectile to its middle section is secured by being screwed into the fuze and venturi adapter. A spun glass sleeve insulates the venturi tube from the explosive charge which is cast on the resulting assembly. A Zt. Z. S/30 time fuze set to operate 19 seconds after the projectile is fired is screwed into the nose of the projectile. Two percussion fuzes, AZ 4331, are located in the venturi adapter. These are armed by the burning of the rocket propelling charge through a powder pellet incorporated in the fuze. The rocket propellant is moulded as one piece, and extending through it are eight longitudinal holes 3/4-inch in diameter, located around a circular hole 1 5/8-inch in diameter.

SPECIFICATIONS

Length of projectile (less fuze)       48.79 ins.
Diameter of ribs 11.70 ins.
Diameter of rotating band 11.85 ins.
Diameter of body 11.10 ins.
Total weight 545 3/4 lbs.
Rocket propellant weight 43 lbs.
Explosive weight 30 3/4 lbs.
Maximum range 93,100 yds.

German: p. 312.1 (June 1, 1945)

Categories
German

28 cm Rifled Projectile

German 28 cm Rifled Projectile

This pre-engraved projectile recovered in Italy is used for long range bombardment. It has longitudinal inclined steel splines and a single one-inch-wide copper band that acts as a gas seal. The splines are set at a slight angle to the axis of the projectile and are 19.2 inches in length. In loading the projectile, the splines are lined up with the rifling of the gun tube. The shell is 33 inches in length, exclusive of the windshield. Fragments indicate that the windshield would add an extra two feet to the length.

A nose percussion fuze (AZ 35 K) and a base fuze (BD Z 35K) are fitted. The Germans are reputed to have four types of 28 cm railway guns able to employ this type of projectile. They are: 28 cm Br. N. Kan E.; 28 cm K. 5 (E); 28 cm K. 5/1 (E); and 28 cm K. 5/2 (E).

SPECIFICATIONS

Caliber         280 mm (11.023 ins.)
Weight (approx.) 550 lbs.
Length (excluding windshield) 33 ins.
German: p. 312

Categories
German

10.5 cm HL, HL/A, HL/B, HL/C: Hollow Charge Ammunition

10.5 cm HL, HL/A, HL/B, HL/C: Hollow Charge Ammunition

There are four known variations of the 10.5 cm (105 mm) hollow charge ammunition fired from the German 10.5 cm le. F. H. 18 series:

Type Hl has a deep conical cavity, a short ogive, and flash tube extending through the shaped cavity to the fuze booster. All types have an additional detonator booster combination at the base of the flash tube.

Type Hl/A has the same shaped cavity but has a larger diameter flash tube that is attached to the apex of cavity liner by a pressed collar, and does not extend into the cavity. This type has a long ogive.

The principal difference between types Hl/A and Hl/B is in a shallower, hemispherical-shaped cavity. The principal difference between types Hl/B and Hl/C is the addition of a funnel-like steel washer inverted over the cavity. This funnel is supposed to counteract the effects of centrifugal force on the hollow charge jet.

The explosive filler is pressed into two pellets in types Hl/A, Hl/B, and type Hl/C. Explosive fillers in all rounds are inclosed in waxed paper cartons. The metal ogive screws into the projectile, holding all components of the filler in place.

The aluminum fuze (AZ 38) carries the primer detonator. It is armed by centrifugal force and contains no other safety features. It functions by a “spit” from the booster, which travels down the central tube and initiates the base booster, and hence the main bursting charge.

ESSENTIAL MODIFICATIONS

Type Hl/A: (a) Lengthened nose-piece (ogive), giving greater standoff. (b) Elimination of flash tube between fuze and apex of cavity and larger diameter of flash tube.

Type Hl/B: (a) Further increase of standoff obtained by shortening the HE filler. Nose piece is identical with that of Type Hl/A. (b) Hemispherical cavity instead of rounded cone. (c) HE filling RDX/WAX, instead of RDX/WAX/TNT.

Type Hl/C: Introduction of a washer, shaped like an inverted funnel in front of the cavity. Otherwise, types B and C are essentially identical.

SPECIFICATIONS

        Hl       Hl/A       Hl/B       Hl/C
Weight of projectile as fired:25.8 lb.27.1 lb.26.6 lb.27.2 lb.
H.E. filling, carton, wax: 4.6875 lb.3.5 lb.3.255 lb.
Empty shell: 22.55 lb.22.937 lb.22.315 lb.
Collar (“funnel”)   .5195 lb.
Muzzle velocity f/s*1375136013601360

Estimated performance at normal against Homogeneous armor.
     Type Hl/A—170 mm (static) 105 mm (dynamic)
     Type Hl/B—155 mm (static) 100 mm (dynamic)
     Type Hl/C—155 mm (static) 100 mm (dynamic)
                       (From German claims)

*Firing with charge five which is normally used.

German: p. 310 (August 1, 1945)

Categories
German

15 cm Stielgranate: 15 cm Stick Grenade

15 cm Stielgranate: 15 cm Stick Grenade

The German 15 cm high explosive Stick Grenade is reported to be used with the 15 cm heavy infantry gun, s. I. G. 33. Its prime purpose is for demolition, and for clearing minefields and wire obstacles. Of welded steel construction, the bomb has a 1/8-inch case consisting of three main parts: the nose, a cylindrical center piece, and a tapered rear piece. Both the nose and the base are reinforced with steel rings welded to the casing. The ring in the nose is tapped to receive the fuze adaptor; that in the base to accommodate a steel cup. This cup, which has machined surfaces, is 3/8-inch thick at the base and 3/16-inch at the sides. A stick unit which leaves the bomb approximately 150 yards from the muzzle of the gun fits over the cup. According to reports, the unit weighs 22.2 kg. (49 lb.) and the propelling charge 5.5 (12 1/8 lb.).

The main filling consists of approximately 60 pounds of poured 50/50 Amatol. A 2-inch cylindrical booster charge made up of compressed T.N.T. pellets is located in the center of the main filling about 15 inches from the booster; two normal annular picric pellets surround the booster. The bomb is fitted with a percussion type nose fuze, Wgr. Z. 36, which is also reported as being used in the German 20 cm Spigot Mortar Bomb. The tail, of unusual construction, has three tubular steel sockets equally spaced around the bomb and projecting from the rear portion of the casing at an angle of 20° to the main axis. These sockets receive tubular bars to which the sheet steel tubular fins are attached. The bars are bent in order to bring the fins parallel to the main axis and also to provide clearance of the muzzle of the gun. In addition there are six 5/32-inch steel plate fins welded to the casing and spaced in pairs between the tubular sockets.

SPECIFICATIONS

Overall length        50 1/2 ins.
Overall length (excluding tail fins & fuze) 30 3/4 ins.
Diameter (maximum) 11 1/2 ins.
Thickness of casing 1/8 in.
Total weight (approx.) 105 lb.
Weight of filling (approx.) 60 lb.
Color Field grey

German: p. 306.1