Tag Archive for 'antitank gun'

7.5/5.5 cm Pak 41: Tapered Bore Antitank Gun

7.5/5.5 cm Pak 41: Tapered Bore Antitank Gun

The 7.5 cm Pak 41, Germany’s latest antitank gun to be brought into service, is designed on the Gerlich or tapered-bore principle. The bore tapers from 7.5 cm at the breech to 5.5 cm at the muzzle, but the taper is not constant. The first part of the bore is cylindrical and rifled; the second, conical and unrifled; and the third, measuring 27.6 inches in length, is cylindrical and unrifled. There is also a muzzle brake. The life of the barrel is estimated at approximately 500-600 rounds. The weapon is long, low, and sturdy in appearance and has a semi-automatic breech mechanism of the vertical wedge type.

The carriage has a split trail and is mounted on metal wheels with solid rubber tires. As traction is by motor tractor, the carriage is fitted with pneumatic brakes controlled by the driver of the tractor. Torsion bar suspension is automatically cut out when the trails are opened.

An elevating mechanism of the sector type is on the right-hand side of the cradle, and a traversing mechanism of the screw type on the left. There is no equilibrator mechanism. The recoil mechanism contains a hydraulic cylinder and spring-type recuperator.

The sighting system, which is graduated up to 1,500 meters (1,635 yards), has four scales for use according to the actual muzzle velocity of the gun. Muzzle velocity drops considerably because of wear.

SPECIFICATIONS

Caliber           7.5/5.5 cm
Weight in action         1.4 tons
Length of barrel (approx.)         170 ins.
Muzzle velocity (estimated)         4,123 f/s
Elevation         -10° to 18°
Traverse         60°
Armor penetration—A.P.C.

       Range in yards          Thickness of armor in inches 
                   Normal               30°    
       500  6.67  5.75  
       1,000  5.94  5.12  
       1,500  5.28  4.49  
2,000  4.63  3.94  

German: p. 123

2.8/2.0 cm Pz. B. 41: Tapered Bore Antitank Gun

2.8/2.0 cm Pz. B. 41: Tapered Bore Antitank Gun

The German antitank gun, Pz. B. 41, captured in the vicinity of Halfaya Pass during the Libyan campaign in 1941, is the first tapered-bore weapon to be found in combat use. Served by a five-man crew, it is normally towed on a trailer, but can be broken down into five loads and transported on a truck or in an airplane.

The tube, which is of heavy monobloc or cold worked construction, is modeled on the Gerlich principle—that is, it is tapered from 28 mm at the breech to 20 mm at the muzzle in order to increase the velocity. No provision is made for cooling the barrel, which is good for about 400 rounds. The forward end of the tube has a muzzle brake threaded to it; the back is attached to the breech ring by an interrupted screw arrangement.

The firing mechanism, of the inertia type, consists of the firing-pin, firing-pin guide, spring and retainer. A breechblock of the horizontal sliding block type is actuated, after cocking, by an operating handle attached to the top of the breech ring.

Both the carriage and pedestal are of welded construction. Shields fixed to the carriage by metal hooks and spring plungers are constructed of steel plates about 3/8 inch thick. Detachable trunnions for fastening the gun and recoil mechanisms to the pedestal permit quick assembly and breakdown of the piece.

The wheels are of the perforated disk type and have pneumatic tires mounted on them. These tires, which are probably Lynthetic, have no valve stems, indicating that they are filled with a cushioning material.

The trails are of the split type and can be locked together or spread at an angle of about 45°.

The gun is flexible on its mount, and as no elevating or traversing gears are employed, these operations are most likely manual. A straight tube telescope is used.

SPECIFICATIONS

Caliber            28 mm at breech
20 mm at muzzle
Weight (complete) 491 lb.
     (tube) 76 lb.
     (barrel & brake) 80 lb.
Length of barrel 61.36 ins.
Breech mechanism Horizontal sliding block
Firing mechanism Inertia type
Recoil mechanism Hydro-spring
Normal recoil 9.34 ins.
Rate of fire 8 to 10 rds./min.
Muzzle velocity 4,550 f/s
Range (effective) 500 yds.
Ammunition A.P. (9,754.4 grs.)
Peneration

        Range       Thickness of armor in inches
Yards         30°         Normal
1002.73.3
2002.53.0
3002.22.8
400       2.1       2.6

German: p. 131

7.5 cm Pak 97/38: Antitank Gun (Ex-French)

7.5 cm Pak 97/38: Antitank Gun (Ex-French)

The 7.5 cm Pak 97/38, introduced by Germany in 1942, consists of the 7.5 cm French Model ’97 equipment which was modified in 1940 as an antitank gun, and the German 5 cm Pak 38 carriage. The built-up tube, to which a Solothurn type perforated muzzle brake is fitted, has four hoops sweated on for additional strength.

The breechblock is the Nordenfeld eccentric screw type commonly used in the French 75 mm tube. The high-pressure, hydropneumatic recoil mechanism contains a floating piston with nitrogen gas in the recuperator cylinder which brings the gun back into battery. The recoil cylinder is of smaller diameter and contains the piston rod which recoils with the tube and forces the recoil oil into the recuperator cylinder where throttling checks the rearward movement of the tube.

The elevating and traversing mechanisms are located on the top carriage; the elevating handwheel is slightly in front of and to the left of the traversing handwheel. There is a single hydropneumatic equilibrator at the right trunnion. The protecting armor consists of two sheets of 4 mm steel plate curved to envelop the front of the weapon. Below the spaced armor is an 8 mm hinged apron. There is also a small shield above the apron that moves with the tube in elevation.

The sighting gear, which is the same as that used with the 5 cm Pak 38, is situated on an arm and bracket which move with the left trunnion. An opening in the shield allows vision for sighting instruments.

The low-slung, light-weight carriage has relatively short split trails of tubular steel. The wheels are of small diameter spokes made of compressed steel and entirely covered with buna rubber tires 4 inches wide. They are independently mounted to absorb traveling shock by free wheeling action. When the trails are spread, however, the free wheel movement is locked by a bracket so the gun will not bounce on firing. A third wheel supports the rear of the trails for transportation.

SPECIFICATIONS

Caliber         75 mm (2.95 ins.)
Weight (complete) 2,870 lb.
Length of tube & breech ring 8.8 ft.
Length (overall) 15 ft.
Breech mechanism Eccentric screw
Firing mechanism Percussion hammer
Recoil mechanism Hydropneumatic
Rifling 20 lands and grooves; R.H. twist
Muzzle velocity (reported) 2,100 f/s
Elevation 18°
Depression 10°
Traverse 60°
Ammunition H.E.; A.P.-H.E.; Hollow charge
Also some Polish types of ammunition
Penetration 60 mm @ 900 yds., 30°

German: p. 121

7.62 cm Pak 36 (r): Antitank Gun (Ex-Russian)

7.62 cm Pak 36 (r): Antitank Gun (Ex-Russian)

The original 7.62 cm Pak 36, a Russian weapon, was captured by the Nazis and modified to increase the velocity. The built-up tube was rebored to seat a longer cartrige case, and a two-baffled muzzle brake added to cut down recoil energy. The breech mechanism is of the vertical sliding type, and the firing mechanism of the continuous pull type. The breech ring has been bored to seat a safety lock which holds the firing mechanism in a safe or firing position. A firing lever attached to the left side of the cradle enables the gunner to traverse as well as fire the piece. The elevating handwheel is generally situated on the right side of the cradle. Two puller type equilibrators located under the front of the cradle and attached to the rear by chains compensate for muzzle preponderance.

The carriage is of welded steel construction with synthetic filled pneumatic tires and split trails, which can be spread to an angle of 60 ° for firing. The hydropneumatic recoil system consists of two cylinders, one for recoil and the other for counterrecoil. This model is semi-automatic in operation.

The weapon is reported to use the following types of ammunition: A.P.C.; H.E. A sight bracket is attached to the left of the trunnion, and the German range indicator is graduated for the types of ammunition mentioned above.

SPECIFICATIONS

Caliber         76.2 mm (3 ins.)
Weight (complete) 3,564 lb.
Length of gun (overall) 23 ft., 5 ins.
Length of tube 12 ft., 1 in.
Carriage Steel split trails with rubber tires
Breech mechanism Vertical sliding block
Firing mechanism Continuous pull
Recoil mechanism Hydropneumatic
Rifling 32 lands & grooves; R.H. twist
Elevation 72°
Depression -4°
Traverse 27° right; 30° left
Penetration

  Range        Thickness of armor in mm
  Yards           30°         Normal
P.B.   4.1 5.2
500   3.7 4.6
1000   3.2 4.1
1500   2.9 3.6
2000   2.5 3.1
2500   2.2 2.8
M.V. 2430 f/s
Wt. of shell 16.7 lb.

German: p. 116

7.62 cm F.K. 39 (r): Antitank Gun (Ex-Russian)

7.62 cm F.K. 39 (r): Antitank Gun (Ex-Russian)

This gun, recently captured in Sicily, has the general simplicity of design characteristic of most Russian weapons. This was formerly a Russian piece, modified by the Germans to use Pak 36 (r) ammunition. The tube which is provided with a jacket is shorter than the Russian 7.62 cm F.K. 36, and is fitted with a double baffled muzzle brake, similar to that used on the 7.5 cm Pak 40. The breechblock is of the vertical falling block type, and appears to be wholly hand operated.

The buffer is located inside the cradle, whereas the recuperator is mounted above the piece. On recoil, the recuperator cylinder moves with the barrel, the piston rod being attached to the upper end of the bracket which is secured to the forward end of the cradle.

Sighting gear consists of a range drum (calibrated for use with Pz. Gr. 40 and Pz. Gr. 39 ammunition) and dial sight carrier mounted on the left trunnion. There appears to be no provision for a telescopic antitank sight.

Traversing and elevating mechanisms are operated by handwheels on the left and right hand sides of the gun.

The weapon is mounted on a crosshead consisting of a short hollow rectangular shaft provided with bearings at either end for the trail heads. The split trails, constructed from rectangular girders, are operated by traversing handles secured to each trail end. Wheels are disk type with pneumatic type tires filled with synthetic.

The shield is a single flat sheet of metal cut away at the lower corners for the wheels. The top is curved upward to the center where there is a sliding center piece over the barrel. A rectangular sighting aperture with sliding cover is cut out on the left hand side in front of the dial sight carrier.

SPECIFICATIONS

Caliber         76.2 mm
Length (overall with muzzle brake) 11.4 ft.
Length of barrel (including breech ring) 10.4 ft.
Length of barrel 299 cm (9.8 ft.)
Rifling 32 lands and grooves; R.H. twist
Length of rifling 215 cm (7.05 ft.)
Max. range 14,216 yds.
Wt. in action 3,535 lb.

German: p. 115

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

8.8 cm Pak 43/41: Antitank Gun

8.8 cm Pak 43/41: Antitank Gun

The Pak 43, one of Germany’s newer antitank guns, is a more solidly built weapon than the 7.5 cm Pak 40. The gun is mounted on large rubber-tired metal wheels. A sloping double shield, 6 feet, 3 inches in height, is fitted to the carriage for the protection of the gun crew. Split trails, approximately 12 feet long, are also supplied.

A muzzle brake is fitted to the barrel. The semi-automatic breech mechanism of the horizontal sliding block type is operated by a small auxiliary cylinder on the left side of the breechblock.

The buffer and recuperator are contained in one cylinder which is fitted above the barrel; the balancing cylinders are mounted vertically on either side of the carriage.

The sight bracket is marked for 8.8 cm Pak 43/41 and 8.8 cm Pak 43 Sfl. This marking tends to confirm the opinion that the Pak 43 is a modification of, or development from, the 8.8 cm Flak 41, which it resembles superficially. This marking also confirms the information that this gun, with the designation 43/1, is used in the self-propelled piece Pz. Jag. III/IV (the “Hornet”).

SPECIFICATIONS

Caliber         88 mm (3.46 ins.)
Weight of gun 4.8 tons
Length of piece (including muzzle brake) 21 ft.
Diameter of wheels 4 ft., 6 ins.
Recoil (maximum) 2.46 ft.
Muzzle velocity Not known
Range Not known
Elevation 38°
Depression -5°
Traverse 58°
Ammunition A.P.C.: H.E.; Hollow-charge
Height 6 ft., 3 ins.

German: p. 113

7.5 cm Pak 40: Antitank Gun

7.5 cm Pak 40: Antitank Gun

The Pak 40, an antitank and antipersonnel weapon, has a barrel of monobloc con­struc­tion to which is screwed a two-baffled muzzle brake. The horizontal sliding type breechblock operates semi-automatically. Recoil and counterrecoil are effected by means of a hydraulic buffer and a hydropneumatic recuperator.

The welded steel carriage has tubular trails, light alloy steel wheels with solid rubber tires, and a 5 mm spaced armor shield for the protection of the gun crew. There are two types of brakes: air brakes, which are operated from the prime mover, and hand brakes for placing the gun in firing position.

Although no sighting equipment was captured with the gun, it is assumed that there was a telescopic sight for direct fire, a sight for indirect fire, and an auxiliary open sight. Mounts for these sights are attached to the breechring and the left trunnion.

There is also a gun known as the 7.5 cm Pak 97/40. This gun consists of a French Model 1897 piece mounted on the carriage of a German 7.5 cm Pak 40, but usually on Pak 38 carriage.

A modification of this gun is used on the chassis of the Pz. Kw. II tank and the Czech Pz. Kw. 38 (t) converting these vehicles into gun motor carriages.

The 75 mm tank gun, KwK. 40, used in Pz. Kw. IV is an adaptation of the Pak 40.

SPECIFICATIONS

Caliber       75 mm (2.95 ins.)
Length of tube126.1 ins.
Weight (travelling position)3,350 lb.
Length (travelling position)19 ft.
Length of bore96.89 ins.
No. of grooves32
Width of grooves.175 in.
Depth of grooves.025 ins.
Width of lands.116 in.
Muzzle velocity (A.P.C. shell)2525 f/s
Traverse65°
Elevation+22°
Depression-5°
Length of recoil35.43 ins.
AmmunitionA.P.-H.E.-H.E. hollow charge
Wt. of projectile (A.P.C.)15 lb.

German: p. 117