As the effectiveness of the tank increases, especially as a result of
more powerful armament and greater armor thickness, the development of
antitank weapons is necessarily speeded up. Until recently the largest
caliber German antitank gun (not to be confused with the dual-purpose
AA/AT gun or with the tank gun) was the 50-mm (see fig. 1). However,
the Germans now have a 75-mm antitank gun (see fig. 2), which they
designate as the 7.5-cm Pak 40 .
|Figure 1.—German 50-mm Antitank Gun.|
Although this new long-barreled gun is very similar in appearance to the
standard German 50-mm antitank gun, known
as the 5-cm Pak 38, the
new 75-mm has certain structural differences which may readily be
detected: its shield is angular, and has a flat frontal section with
two flat side pieces set at an angle of about 45° to the plane of
the frontal section; its muzzle brake is broader and longer; and its
sighting aperture is square.
|Figure 2.—German 75-mm Antitank Gun.|
The new 75-mm, exclusive of its carriage, is essentially the same weapon
as the German 75-mm long-barreled tank gun, which the German Army designates
as the 7.5-cm Kw. K. 40  (the latter is now the principal armament of
the Pz. Kw. 4, and also appears in two self-propelled versions.) The chief
differences between the 75-mm antitank gun and tank gun are probably the
substitution, in the antitank gun, of mechanical firing and percussion
primer for electric firing and primer; the chamber of the antitank gun
is also probably much longer. The breechblock is of the semiautomatic,
horizontally sliding type.
The 75-mm antitank gun is mounted on a split-trail carriage, with torsion
springing; this springing is automatically cut out when the trails are
open. The light-alloy wheels are fitted with solid rubber tires. An unusual
feature is a detachable third wheel, which can be fitted on near the trail
spades, to permit easier manhandling. The gun has a double baffle muzzle brake.
Additional details about the weapon are as follows:
|Over-all length in traveling position || _ _ _ _ _ ||19 ft. 2 in.|
|Over-all height|| _ _ _ _ _ ||54 in.|
|Weight in action|| _ _ _ _ _ ||3,350 lbs.|
|Length of barrel || _ _ _ _ _ ||10 ft. 6 in.|
|Length of recoil|| _ _ _ _ _ ||35.43 in.|
|Elevation|| _ _ _ _ _ ||+22 degrees.|
|Depression|| _ _ _ _ _ ||5 degrees.|
|Traverse|| _ _ _ _ _ ||65 degrees.|
Four types of ammunition are used: high explosive, hollow charge,
armor-piercing shot, and an armor-piercing tracer shell with a small
explosive charge and an armor-piercing cap covered with a ballistic
nose. The armor-piercing shot is the usual German steel casing enclosing
a tungsten carbide core; it is fitted with tracer.
Detailed confirmed information regarding the effectiveness of this weapon
is not yet available. It has a low silhouette, certainly, and this is
always a definite advantage for an antitank gun. While the muzzle velocity
is high, the tube is of monobloc construction and the propellant charge
is very large; in view of this, the safety factor may be regarded as
somewhat doubtful. Nevertheless, the Germans apparently have confidence
in the gun, inasmuch as they are now manufacturing it as a standard weapon.
 Panzerabwehrkanone—antitank gun.
 Kampfwagen Kanone—tank gun.