Tag Archive for '5cm'

Pz. Kpfw. III Aus. J, K (Sd. Kfz. 141): Medium Tanks

Pz. Kpfw. III Aus. J, K (Sd. Kfz. 141): Medium Tanks

Model J—The principal differences between Model J and earlier models are:

1. Increased thickness of basic armor plate on certain front and rear plates from 30 mm to 50 mm and the addition of spaced armor on the front of the gun mantlet and the front plate of the superstructure.

2. Hydraulically operated steering in the earlier models has been replaced by mechanical steering. As previously reported, the complicated Maybach Variorex ten-speed gear was abandoned in Model H in favor of a manual six-speed and reverse gear box.

3. Wider tracks—15 inches instead of 14 1/8 inches. The heavier track necessitated a change in the spacing of the return rollers. Front and rear rollers are now mounted directly over the Luvax shock absorbers and prevent the track fouling the latter.

4. The tail plate has been modified to give better protection to the rear air outlet; it also allows the smoke device to be mounted inside the plate.

5. One or two mild steel bars, welded at each end, are fixed across the middle of the nose plate. The track shoes are placed behind the bars and are held in position by the bridge of the shoe.

6. The mounting of the 5.0 cm Kw. K. 39 (long gun) was incorporated in the latest of the Model J tanks.

The most prominent recognition points of this model are: the mounting of the hull machine gun is of prominent ball type; the driver’s visor consists of a single hinged piece of armor instead of two separate plates; the front sprocket and rear idler are similar to those in Model H; particularly squat turret, pear-shaped with circular cupola well set to the rear.

Model K—Same as Model J. This model mounted the 5.0 cm long gun (Kw. K. 39).

SPECIFICATIONS

Weight         22 tons
Length 17 ft., 9 ins.
Width 9 ft., 8 ins.
Height 8 ft., 3 ins.
Ground clearance 15 ins.
Tread centers 8 ft., 2 1/2 ins.
Ground contact 9 ft., 4 1/2 ins.
Width of track 15 ins.
Pitch of track 4 3/4 ins.
Track links 90
Fording depth 3 ft.
Theoretical radius of action:
     Roads 100 miles
     Cross-country 60 miles
Speed:
     Road 28 m.p.h.
     Cross-country 15 m.p.h.
Armor:
     Front plate 50 mm
     Sides 30 mm
Armament 5.0 cm Kw. K. 39
2 MG’s
Ammunition 5.0 cm gun—75 rds.
Engine Maybach HL 120 TRM, V-12, 320 hp.
Transmission Manual, 6 speeds forward, 1 reverse
Steering Epicyclic, clutch brake
Crew 5

German: p. 24

Pz. Kpfw. III Aus. F, G, H (Sd. Kfz. 141): Medium Tanks

Pz. Kpfw. III Ausf. F, G, H (Sd. Kfz. 141): Medium Tanks

Model F—This is the first tank of the series to mount a 5.0 cm Kw. K. electrically fired tank gun in place of the 3.7 cm Kw. K. and also the first to have a new type mantlet. This mantlet has a thick shield on the front which moves with the gun. A single machine gun is mounted coaxially on the right of the 5.0 cm gun and the hull machine gun is retained.

The hull consists of three separate subassemblies: (1) lower hull, (2) front superstructure carrying turret, and (3) rear superstructure covering the engine compartment. All units are of single skin welded construction.

The turret forms the roof of a spacious fighting compartment, being mounted over the middle part of the hull. It has no rotating platform, the commander and the gunner having seats suspended from and rotating with the turret. The loader apparently stands on the floor of the fighting compartment. The commander’s cupola is bolted to the roof of the turret on the center-line to the rear.

The suspension is the same as that used in Model E.

The engine is the Maybach V-12, gasoline, rated 320 hp. Its transmission is the synchromesh type with 10 speeds forward and 4 reverse. Its steering is of the epicyclic, clutch brake type with hydraulic control.

Model G—Identical in armament, mantlet, and mechanical components to Model F, the only difference being in the cupola, which is more squat and has all-around vision.

Model H—This model has additional 32 mm plates bolted on the front of the superstructure, on the upper and lower nose plates and on the tail plate. The outstanding recognition features of this model are its front sprocket which has six spokes, and its rear idler which is more open than the earlier type, though it has eight spokes. Wider tracks and narrower bogie wheels are also used.

SPECIFICATIONS

Weight         22 tons
Length 17 ft., 9 ins.
Width 9 ft., 7 ins.
Height 8 ft., 3 ins.
Ground clearance 15 ins.
Tread centers 8 ft., 1 7/8 ins.
Ground contact (approx.) 10 ft., 6 ins.
Width of track 14 1/8 ins.
Pitch of track 4 3/4 ins.
Track links 90
Fording depth 3 ft.
Theoretical radius of action:
     Roads 100 miles
     Cross-country 60 miles
Speed:
     Road 28 m.p.h.
     Cross-country 15 m.p.h.
Armor:
     Front plate 30 + 32 mm
     Sides 30 mm
Armament 5.0 cm Kw. K.
2 MG’s
Ammunition
Engine Maybach, HL 120, V-12, 320 hp.
Transmission Synchromesh, 10 forward, 4 reverse, and 6 forward, 1 reverse.
Steering Epicyclic, clutch brake
Crew 5

German: p. 23

5 cm l. Gr. W. 36: Light Mortar

5 cm l. Gr. W. 36: Light Mortar

The German 5 cm light mortar, developed in 1936, is a compact piece which can be easily broken down into two loads for transport. It differs radically from the conventional mortar design in that it is trigger-fired.

A short, seamless tube is threaded at its base to the breech ring containing the firing mechanism. The firing-pin assembly is actuated by a manually operated trigger, fixed to the rear half of the breech ring. Two large holes in the rear of the ring serve as trunnions by which the mortar is fastened to the cradle, and about which the mortar is elevated.

The forward end of the mortar tube is connected to the base plate by means of two brackets and the elevating mechanism. The front bracket is tightened around the tube by a bolt; the rear one fits around the breech ring and is locked by a set screw.

Two elevating mechanisms, one coarse and one fine, permit a total range of elevation from 43.5° to 90°. A range scale, calibrated in meters from 0 to 525 is screwed to the left side of the breech ring. A hook-shaped lever, pinned to the rear left side of the cradle, rides along the range scale as the elevation of the mortar is changed and serves as an indicator. The combination leveling and traversing mechanism allows a total traverse of 30°, 15 to the right and left, respectively. Center traverse is indicated by an arrow, pointing to an “0” engraved on the rear top of a ball joint about which the cradle traverses.

The base plate, constructed of sheet metal, is reinforced by ribs welded to the bottom side. Two ribs, serving as the main spades, are set at an angle of 23° from the vertical at front and rear of the plate. Reinforcing ribs, welded perpendicularly to the base plate and running lengthwise as well as crosswise, also act as spades.

SPECIFICATIONS

Caliber         50 mm (1.969 ins.)
Weight (complete) 31 lb.
Length of tube 13.75 ins.
Mount Cradle and base plate, no bipod
Firing mechanism Trigger-operated
Method of loading Muzzle
Muzzle velocity 230 f/s
Range (maximum at 45° elevation) 550 yds.
(minimum at 85° elevation) 50 yds.
Elevation (maximum) 90°
       (minimum) 43.5°
Traverse 30° (15° right; 15° left)
Elevating and traversing mechanisms Enclosed, well-sealed
Direct-sighting equipment None
Cross leveling system, Operated by leveling knobs and bubble
Ammunition         H.E. (equipped with fin assembly, point-detonating fuze, & booster). Wt. 2.00 lb.

German: p. 124

5 cm Pzgr. patr. 40 Pak: 5 cm Arrowhead Ammunition

5 cm Pzgr. patr. 40 Pak: 5 cm Arrowhead Ammunition

This fixed round of ammunition is fired from the old model of German 5 cm short-barrel tank gun. The projectile has a plastic needlepoint ballistic cap, a mild steel projectile body, a tungsten carbide core, and a tracer. The cartridge case contains a propelling charge of diethylene glycol dinitrate tubular stick powder, and a charge of nitrocellulose granular igniter powder. An electric primer containing a quickmatch and black powder charge is also used.

The center of the projectile body is trimmed down, lightening the round and giving the ammunition an extremely high muzzle velocity. Armor-penetrating qualities are very good, but can be used only for short ranges due to the instability of the projectile in flight. On impact with armor plate, the plastic ballistic cap shatters and the tungsten carbide core is the only part that penetrates.

The projecile is unusual in that the forward bearing surface acts as the rotating band, and the rear bearing surface as the bourrelet. The rear bearing surface is in two parts, due to the crimping groove dividing it.

SPECIFICATIONS

Weight of complete round         5 lb., 3 oz.
Weight of projectile as fired 1 lb., 15.86 oz.
Weight of tracer composition (kind not known) 0.12 oz.
Weight of primer composition (quickmatch and black powder) 0.07 oz.
Weight of igniting charge (nitrocellulose granular) 0.45 oz.
Weight of propellant 1 lb., 2.69 oz.
Length of complete round (overall) 14.480 ins.
Length of projectile w/tracer cup 5.75 ins.
Length of cartridge case 11.342 ins.
Diameter of bourrelet 1.950 ins.
Diameter of rotating band 2.269 ins.
Diameter of body midway of projectile 1.258 ins.

German: p. 307

5 cm Pak 38: Antitank Gun

5 cm Pak 38: German Antitank Gun

The 5 cm Pak 38, introduced during the 1941 campaigns in Greece and Egypt, was developed to combat the more heavily armored vehicles of the Allies.

The gun has a barrel of monobloc construction, threaded at the muzzle for attaching a two-baffled muzzle brake. Because of the position of the breech-operating cam, a minimum length of recoil of approximately 18 1/2 inches is needed to operate the semi-automatic breech mechanism which is of the sliding horizontal block type. The recoil recuperator system is hydropneumatic.

The carriage, constructed of welded steel, is mounted on metal disk wheels with solid rubber tires. Torsion bar suspension is automatically locked when the tubular trails are spread. A 5 mm spaced armor shield and single apron protect the gun crew. The left side of the shield has a sighting port.

There are five types of ammunition fired from the Pak 38: an armor-piercing capped, high-explosive projectile; a high-explosive shell; an A.P.-H.E. (uncapped) shell; a tungsten carbide core arrowhead type projectile (A.P. 40), and a stick grenade similar to the 3.7 cm grenade described on page 306.

SPECIFICATIONS

Caliber     50 mm (1.97 ins.)
Weight (complete)2,015 lbs. (approx.)
Length of gun (overall) 15 ft., 3 ins.
Length of barrel (overall)9 ft., 3 ins.
Width C-C 5 ft., 1 in.
CarriageWelded steel w/solid rubber tires and tubular trails
Breech mechanismHorizontal sliding block
Recoil mechanismHydropneumatic
Rifling20 lands & grooves; right-hand twist
Muzzle velocity
   A.P.C.-H.E. 4.5 lb.—2600 f/s
   H.E. 4.0 lb.-1800 f/s
Elevation 22°
Depression -4°
Traverse 80°
Sights Straight tube telescope
AmmunitionA.P.; A.P.C.; H.E.; A.P. 40
Penetration

         Range Thickness of armor in mm
 Yards        30°       Normal
 5002.63.1
 7002.42.9
10002.22.6
12002.02.5

German: p. 126 (June 1, 1945)

5 cm Flak 41: Antiaircraft Gun

5 cm Flak 41: Antiaircraft Gun

This gas-operated, automatic, antiaircraft gun is transported on two-wheeled transporters. To put the gun into action, the platform is lowered from the transporters by means of winding gear. The two transverse legs are lowered and the platform is roughly leveled with jacks. The final leveling is done with leveling screws in the base ring of the mounting. The barrel is removable for easy replacement in the field. The right hand twist of the rifling increases from one in 36 1/2 to one in 30 calibers.

The breech mechanism is similar to that of the 3.7 cm Flak 43. It differs in that the breech block drops into the closed position from the open position. The dropping of the block allows buttress guides on the block to engage with similar guides on the jacket. This locks the block in the firing position and prevents any rearward movement. The feed mechanism is operated by the recoil of the breech casing. The recuperator consists of two spiral springs which are mounted side by side in the cradle. The buffer is mounted centrally in the cradle.

The traversing gear and the sight are on the right hand side of the mounting. The sight bracket is connected by means of a parallel motion link to a cross shaft. Here it is keyed to a pointer on the elevation scale. The gun elevating gear is on the left side of the mounting. This is also connected to a pointer on the elevation scale. The layer keeps the two pointers in line and the gun is laid at the same angle of elevation as the sight.

SPECIFICATIONS

Caliber       5 cm (1.97 ins.)
Weight (traveling position) 7.18 tons
Weight (firing position) 4.30 tons
Length (traveling position) 27 ft., 5.5 ins.
Length (firing position) 19 ft., 10 ins.
Height (traveling position) 7 ft., 1 in.
Height (firing position) 7 ft., 4 ins.
Width (overall-traveling) 7 ft., 10 ins.
Width of trail spread
Length of gun (incl. muzzle brake) 184.5 ins.
Length of gun (excl. muzzle brake) 170.8 ins.
Length of rifling 117.28 ins.
No. of grooves 20
Width of grooves 0.160 in.
Depth of grooves 0.020 in.
Width of lands
Muzzle velocity (H.E. shell) 2,756 f/s
Firing mechanism protrusion 0.1 in.
Max. range (horizontal), APCBC 11,300 yds.
Max. range (vertical), APCBC 8,600 yds.
Effective ceiling 10,000 ft.
Rate of fire 130 r.p.m.
Traverse 360°
Elevation 90°
Depression -10°
Length of recoil 7 ins. (approx.)
Ammunition H.E. 41/tracer; Incendiary/H.E. 41/tracer; A.P.C.B.C. 42
Wt. of projectile H.E.—4.8 lbs.
  A.P.—4.87 lbs.
Tracer burn out point Short (8 sec.) 2,740-3,750 yds.
  Long (18 sec.) 5,400-6,120 yds.

German: p. 125 (June 1, 1945)