Tag Archive for '47mm'

Pz. Jäg. I für 4.7 cm Pak (t): S.P. Antitank Gun (Czech)

Pz. Jäg. I für 4.7 cm Pak (t): S.P. Antitank Gun (Czech)

This equipment, which is primarily a tank-hunter, was created by combining the 4.7 cm Czech antitank gun with the chassis of the Pz. Kpfw. I, Model B tank. Consequently its road performance approximates that of the Model B tank.

The turret arrangement consists of a three-sided welded shield, open at the top and rear, bolted to the superstructure by means of internal flanges. The driver’s seat is on the floor to the left rear of the gear box.

The fitting of the gun to the chassis is crude in many respects and not up to the usual standard of German workmanship or design. The gun is mounted on a steel frame, within the shield, in the front half of the vehicle. It is a single shot, high velocity weapon. The barrel is a one-piece forging fitted with a large and heavy muzzle brake and flash eliminator. The breech mechanism is of the vertical sliding block type. The gun is automatically cocked when the breech is opened. The elevating gear is on the left hand side of the gun and is controlled by an elevating wheel with a folding handle. The traversing gear is behind the elevating hand wheel. Traverse is limited by a spring-loaded stop to 15 deg. left or right. The recoil mechanism, which consists of a spring recuperator and liquid buffer, is housed in a cylindrical casing above the piece.

The gun utilizes the following types of ammunition—(1) A.P. tracer shell, (2) H.E. shell. At 300 yards the A.P. projectile effects a penetration of homogeneous armor of 2.3 ins. at 30 deg. obliquity; 3.0 ins. normal, and at 1000 yards will penetrate 1.8 in. at 30 deg. obliquity; 2.4 ins. normal.

SPECIFICATIONS

Weight         8.4 tons
Length 14 ft., 6 ins.
Width 6 ft., 9 ins.
Height 7 ft.
Ground clearance 11 1/2 ins.
Tread centers 5 ft., 8 ins.
Ground contact 8 ft.
Width of track 11 ins.
Pitch of track 3 11/16 ins.
Track links 99
Fording depth 2 ft.
Theoretical radius of action
     Roads 87 miles
     Cross-country 72 miles
Speed
     Roads 26 m.p.h.
     Cross-country 15 m.p.h.
Armor
     Front plate 15 mm
     Sides 10 mm
     Shield 15 mm
Armament 4.7 cm. Pak (t)
     Muzzle velocity (AP) Wt. 3.6 lb.—2540 f.s.
(HE) 1300 f.s.
     Effective range (HE) 1520 yds.
     Overall length 187.5 ins.
     Traverse 30°
     Elevation 12°
     Depression
Ammunition (rds.) 74
Engine 100 h.p. 6-cyl. Maybach Model NL 38 TR
Transmission 5 speeds forward, 1 reverse
Steering Clutch brake
Crew         3

German: p. 4

4.7 cm Pak (t) (Skoda): Antitank Gun (Ex-Czech)

4.7 cm Pak (t) Skoda: Antitank Gun (Ex-Czech)

The 4.7 cm Skoda semi-automatic, antitank gun is now apparently obsolescent.

The tube, of monobloc construction, is threaded to take a single baffled muzzle brake and flash hider; the rear is screwed on to the breech ring. The gun recoils on vertical slides riveted to the piece. The breechblock is of the vertical sliding wedge type. The piece is cocked automatically when the breechblock is opened, but provision for cocking by hand is also made.

The recoil mechanism, housed in a cylinder above the piece, consists of a spring recuperator and a buffer cylinder containing water and glycerine.

The top carriage which pivots in traverse on the lower carriage consists of a circular steel base housing machined to hold the trunnion seats for the cradle. The traversing mechanism consists of a handwheel, flexible joint, worm and worm wheel. A grip handle acts as a separate clutch for disengaging the free traverse. The elevating mechanism has a handwheel, beveled gears, flexible joints, shaft, worm and worm wheel.

The carriage has split trails of welded steel construction spread to an angle of about 52° for firing support. In traveling position, they are locked to the axle, and the piece which is rotated through an angle of 180° rests over the trail legs. The wooden-spoked wheels are fitted with steel rims and mechanical brakes which are operated by a hand lever.

The shield is rectangular with a double curve on the top and a cut-away portion for the wheels on either side. It is constructed of a thin 5 mm sheet of armor and has a rectangular sighting aperture on the left-hand side.

SPECIFICATIONS

Caliber         47 mm (1.85 ins.)
Weight (complete) 800 lb. (approx).
Length (overall), (travelling position) 162 ins.
Length of tube 6.25 ft.
Breech mechanism Vertical sliding wedge; semi-auto.
Firing mechanism Inertia
Recoil mechanism Hydro-spring
Rifling 20 lands and grooves; R.H. twist
Muzzle velocity (A.P.) Wt. 3.6 lb.—2540 f/s
Elevation 30°
Depression -4°
Traverse 45° scaled—360° free
Ammunition H.E.; A.P. (Uncapped)
Penetration

A.P. shot against homogeneous armor
Range Thickness of armor in inches
Yards   30°   Normal
300           2.3         3.0
500   2.2 2.8
700   2.0 2.6
1000   1.8 2.4

German: p. 127

47 mm Tank Gun Type I (1941)

47mm Tank Gun Type I (1941)

The Japanese Type I (1941) 47 mm tank gun is mounted in the Type 97 Improved Medium Tank, replacing the 57 mm tank gun, a weapon of much lower velocity. The 47 mm tank model is very similar to the Type I, 47 mm antitank gun described on page 106. The breech mechanism, however, is of the semi-automatic, vertical sliding block type instead of the horizontal sliding block type. The barrel, 7 feet, 11 1/2 inches long, is of built-up construction. The firing mechanism is of the percussion hammer type, the recoil mechanism is a hydro-spring type.

The piece is free mounted in a mantlet in the turret which permits a total traverse of approximately 15 degrees. Elevation and depression of from 8 to 10 degrees may be obtained. The gun fires high explosive and armor-piercing high explosive ammunition.

Two types of telescopic sights for this gun have been recovered. Although different in size and design, they are both 4 power by 14 degrees.

Firing tests on this gun reveal that A.P.H.E. ammunition at 500 yards will penetrate 2.7 inches of homogeneous armor at normal, and 2.2 inches of homogeneous armor at 30° from normal.

SPECIFICATIONS

Caliber         47 mm (1.85 ins.)
Weight 904 lbs.
Length (overall) 9 ft., 7 ins.
Length of tube 7 ft., 11 1/2 ins.
Length of bore (including chamber) 7 ft., 3/4 in.
No. of grooves 16
Width of grooves
Depth of grooves
Width of lands
Muzzle velocity (A.P.H.E. shell) 2,700 f/s
Max. range
Rate of fire
Traverse 15°
Elevation 8° to 10°
Depression 8° to 10°
Length of recoil
Ammunition H.E. and A.P.H.E.
Wt. of projectile (H.E.) 3.08 lbs.
     (A.P.H.E.) 3.37 lbs.

Japanese: p. 106.1 (August 1, 1945)