Jagdpanzer IV - Development

Development

After the Battle of Stalingrad, in September 1942 the Wehrmacht's arms bureau, the Waffenamt, called for a new standard for assault weapons: 100 mm of armor to the front, 40–50 mm on the sides, wider tracks, ground clearance of 50 cm, top speed of 26 km/h and the lowest possible firing positions. The new Panzerjager ("tank hunter") design would be armed with the same 7.5 cm gun as fitted to the Panther: the Pak 42 L/70. Initially a new chassis was planned, but that of the Panzer IV had to be used.

Previous efforts to mount bigger guns on smaller chassis resulted in the Marder series as well as StuG IIIs. The Marder series were tall and had open crew compartments. The new design had a low silhouette and completely enclosed fighting compartment.

The Jagdpanzer IV used Panzer IV chassis 7 (known as BW7), but the almost-vertical front hull plate was replaced by sloped armor plates. Internally, the layout was changed to accommodate the new superstructure, moving the fuel tanks and ammunition racks. Since the Jagdpanzer lacked a turret, the engine which originally powered the Panzer IV's turret could be eliminated.

The new superstructure had 80 mm thick sloped armour, which gives a much greater armor protection than a vertical armor of 100 mm. To make the manufacturing process as simple as possible, the superstructure was made out of large, interlocking plates which were welded together.

Armament consisted of a 7.5 cm main gun, originally intended to be the Pak 42 L/70, but due to shortages older guns were initially used, the 7.5 cm Pak 39 L/43 for preproduction, and the 7.5 cm Pak 39 L/48 for initial production variant. These were shorter and less powerful than the Pak 42.

Installing the much heavier Pak 42 meant that the Jagdpanzer IV was nose heavy, especially with the heavy frontal armor. This made them less mobile and more difficult to operate in rough terrain, leading their crews to nickname them Guderian-Ente "Guderian's duck". To prevent the rubber rims of the roadwheels being dislocated by the weight of the vehicle, some later versions had steel roadwheels installed on the front.

The final prototype of the Jagdpanzer IV was presented in December 1943 and production started in January 1944, with the Pak 39 L/48 armed variant staying in production until November. Production of the Pak 42 L/70 armed variants started in August and continued until March/April 1945.

On August 19–22, 1943, after the Battle of Kursk, Hitler received reports that StuG IIIs performed better than Panzer IV within certain restraints of how they were deployed. It was thus intended to stop production of the Panzer IV itself at the end of 1944 to concentrate solely on production of the Jagdpanzer IV, but the Panzer IV was in production all the way until the end of the conflict along with Jagdpanzer IV.