German Reich (1941)
Assault Gun – 50 Ausf.C and 150 Ausf.D Built
Following the Ausf.A and Ausf.B, the next vehicles in the line of the highly successful StuG III series were the identical Ausf.C and D. These were mainly introduced to production with some structural changes and improvements to armor protection. Despite the high demand for such vehicles, both of these would be built in rather smaller numbers.

Sturmgeschütz III Ausf.C and D
In mid-September 1940, German Army officials met with the Daimler-Benz representative to consult on the necessary changes to the future StuG III vehicles. The upper gun’s sight aperture was to be removed and the part of the superstructure design was simplified. This necessitated an installation of a new gun sight periscope optic. Following a successful solution, a small production order for the Ausf.C was given. Parallel to the development of the Ausf.C, the German Army requested that additional vehicles should be built to increase the combat strength of available units but also to act as a replacement for lost vehicles. This version, named Ausf.D, was basically a direct copy of the Ausf.C.
Production
Despite the need for such vehicles, only a production order for 50 (chassis number 90551-90600) Ausf.C vehicles was given. The production was to commence in March 1941, but due to some delays in production, it actually started the following month. By May 1941, all 50 vehicles were completed. Also in May, the Ausf.D production began with an order for 150 (chassis number 90601-90750) such vehicles. This production order was completed by September 1941. Both series of the StuG III Ausf.C and D were produced by Alkett.

Design
Visually, both the Ausf.C and D were quite similar to their predecessors. But nevertheless, some changes were implemented. These were mostly aimed to improve the upper superstructure design, protection, and some other minor changes.
Hull
The StuG III Ausf.C and D hull design was unchanged. It was the same as its predecessors with the front-mounted drive unit, central crew compartment, and rear-positioned engine. One quite minor change was the use of a new type of locking mechanism on the glacis hatches that were used by the crew for maintenance.
Suspension and Running Gear
The torsion bar suspension remained the same. It consisted of six small road wheels, three return rollers, the front drive wheel, and the rear positioned idler. The only change to it was introducing a newly designed rear idler wheel, starting from the StuG III Ausf.C.

Engine
The StuG III Ausf.C and D were powered by a twelve-cylinder, water-cooled Maybach HL 120 TRM engine providing 265 hp @ 2,600 rpm engine. Some very minor changes to the engine were made, including new oil bath air cleaners.
Vehicles that were used in North Africa and other warmer climates, such as southern Russia, received additional changes to the engine compartment in order to effectively operate in this challenging theater. This included cutting ventilation ports on the top hatches of the engine compartment and increasing the engine ventilation speed.
Superstructure
The upper superstructure received a number of changes that clearly distinguished them from the previous versions. During its service life, the early StuG III vehicle had a huge weak spot on its frontal superstructure, namely the left aperture that was used by the gunner’s sight. The German Army Official specifically asked for its improvement, which likely led to the creation of the Ausf.C version. This opening was simply enclosed, and the gunner was provided instead with a longer periscope selbstfahrlafette-Zeilenfernrohr (Sfl ZF) sight that would be used from inside the vehicle. The original two top hatches for the gunner’s sight were replaced with one larger hatch. There was also a bullet splash deflector for this hatch placed on the vehicle’s left side.



In addition, the front upper armor plate design was greatly simplified as the previous version used a somewhat unnecessary complicated design. The Ausf.C introduced a much simpler arrangement with singular angled plates. This improved the whole design, providing better protection and greatly simplifying the production of the superstructure.


Armor Protection
The StuG III Ausf.C and D armor protection remained the same as the previous version. It consisted of 50 mm thick frontal armor. The sides and rear were somewhat thinner, at 30 mm. In order to improve the level of protection without adding extra armor, on the Ausf.D, the face-hardening of the frontal armor plates was slightly increased. The crews themselves would add all kinds of stuff that they could get their hands on to their vehicle in the hope of further increasing the protection. For example, some crews added concrete to this end.


Armament
The main armament remained the same as in the previous version. It consisted of a 7.5 cm StuK 37 L/24. It was primarily designed to engage fortified positions using a 7.5 cm Gr Patr high-explosive round. Another round used was the 7.5 cm PzGr patr armor-piercing round with a muzzle velocity of 385 mps, and could pierce around 39 mm of 30° angled armor at distances of 500 m. The elevation of the gun was -10° to +20°, while the traverse was limited to 12° per side. The ammunition load consisted of 44 rounds, mostly stored in front of the loader.
The StuG III’s anti-tank round was more than capable of destroying Soviet tank designs such as the BT series or the T-26. Against the new Soviet designs, such as the T-34 or the KV-series, the use of anti-tank rounds was almost useless. Surprisingly, the high-explosive round was more successful. While it could not penetrate the thick armor of the enemy tank, its explosive firepower was enough to cause serious damage to them by blowing up the suspension or even jamming the gun. By late 1941, due to the ineffectiveness of their anti-tank guns, the Germans were becoming desperate to find a solution. The introduction of tungsten-based ammunition was seen as a simple solution. The downside of it was that Germany was in short supply of this metal. Despite the shortages, anti-tank guns used during this time, such as the 5 cm PaK 38, received this ammunition in limited numbers. Interestingly, due to 7.5 cm L/24’s low velocity, the Germans never developed a tungsten round for this gun.
Instead, they approached this problem from another angle. In December 1941, Adolf Hitler issued an order that the production of the shaped-charge round should begin as soon as possible. This led to the introduction of the 7.5 cm GrPatr38 A and B versions. These had a velocity of 450 mps with the difference that the later version had a slightly better penetration of 75 mm at any range. While on paper this meant that any enemy tank could be defeated, the reality was quite different. For example, the low velocity led to a rather limited accuracy. In addition, the overall ballistic design of this round was far from perfect as it too often simply bounced off or failed to penetrate enemy armor. Interestingly enough, following the introduction of this new ammunition, the production of standard armor-piercing ammunition was discontinued at the end of 1942.

In early 1942, the German 9th Army made a series of firing trials in order to test the new ammunition’s performance. Alongside other available rounds, it was tested against a few different captured Soviet tanks. For example, a KV-2 was targeted at ranges of 150 m at 45° angles of attack. After firing eight rounds (three AP, two HE, and three shaped-charge), all failed to penetrate the armor and the only damage reported was the jamming of the turret. A T-34 was the next target, engaged at a distance of only 70 m at an angle of 60º. After firing four shaped-charge rounds, only the idler and the track were damaged. The same type of round was also fired at the 80 m range. It blew up the T-34’s hatches but two rounds simply bounced off its slope armor. Basically, this type of ammunition had a mixed performance, but was still a welcome addition for the crews that operated these vehicles.
Two MP38 or 40 submachine guns were provided for crew protection.
Crew
The crew of these vehicles consisted of four; commander, driver, loader, and gunner. While the loader was positioned to the right of the gun, the remaining crew were placed opposite. The driver was positioned on the left front side of the hull. Just behind the driver was the gunner, and right behind, the commander.
Organization
In the early years of the Second World War, due to quite limited German industrial capability, the production of new StuG III vehicles was slow. For example, during the German offensive toward France and its allies in May 1940, the 24 available StuGs were distributed to four batteries: the 640th, 659th, 660th, and 665th. Once again, due to a limited number of available vehicles, the Germans were forced to deploy them in small Sturmartillerie Batterie (Eng. assault gun battery). These were divided into three Zuge (Eng. platoons), each equipped with only two vehicles.
In time, as more StuG IIIs became available, their unit strength was increased to Abteilungen (Eng. battalion) strength of 18 vehicles. These battalions were divided into three batteries, each 6 vehicles strong. These would be further reinforced by three additional vehicles which were allocated to the platoon commanders.
In Combat
The StuG IIII Ausf.C and D were used to either replace losses, of which some 105 were reported in 1941, or supplement the creation of new units. Given the use of four quite similar series, sources have rarely made an effort to mention the precise versions used in combat. Given that their production run began in April and ended in September 1941, this meant that the majority of them went to the Eastern Front.
In the Soviet Union
For the Invasion of the Soviet Union in June 1941, the Germans managed to form 12 assault gun battalions with 5 additional batteries. These were divided into the three Heeresgruppen (English: army groups): Nord (English: North), Mitte (English: Center), and Süd (English: South). Given as it was expected that the majority of the fighting was to be carried out by the Army Group Center, eight assault battalions were allocated to this part of the front, including 177th, 189th, 191st, 192nd, 201st, 203th, 210th, and 226th. The Army Group North received five batteries (659th, 660th, 665th, and 667th) supported by two battalions (184th and 185th). The remaining two battalions (190th and 197th) were later reinforced by the 202nd and 209th battalions participating in the South Army Group.
In the early stages of the war with the Soviets, the StuG vehicles achieved great success. For example, the commander of an unspecified unit, Oberfeldwebel Rudolf Jaenicke, is credited to have destroyed some 12 Soviet BT-2 tanks. Another successful commander was Oberleutnant Peter Frantz, whose unit took part in the heavy fighting for Tula in December 1941. His unit managed to destroy some 15 Soviet tanks in one day of fighting.
The 667th batterie particularly performed very well, during the battle for the approach to Leningrad. During the advance toward their targets, this batterie saw heavy action while supporting infantry formation from the 1st Corps. Thanks to the efforts of the 667th batterie and its commander, Oberleutnant Joachim Lutzow, the following enemy losses were reported to be achieved during the period of 12th to 19th September 1941: some 225 bunkers destroyed, including 301 heavy weapons and machine gun nests. In addition, 6,500 enemy soldiers were taken captive with 92 guns being captured. For this effort, Oberleutnant Joachim Lutzow was awarded the Knight’s Cross Medal. Kurt Kirchner, who during early 1942 is credited with destroying 30 Soviet tanks, was also part of this unit.

The harsh winter and the stiff Soviet resistance during 1941 led to losses among the StuG III units. Nevertheless, a substantial number of the short-barreled version survived and were used extensively in 1942. For example, the 244th battalion, during the Second Battle ofKharkov in May 1942, was reported to have helped destroy some 86 Soviet tanks (T-34 and KV-1 and KV-2). This was possible thanks to the use of the shape-charged rounds. The unit later reported that this type of ammunition was effective, often igniting the destroyed vehicle. The effectiveness of the StuG III vehicles was such that, reportedly, on numerous occasions, the Soviet forces simply ran away after seeing the German vehicles approaching them.


In North Africa
Somewhat surprisingly, the StuG III in North Africa was quite a rare sight. The first StuG III that was used on this front were three Ausf.D. These were allocated to Sonderverband 288 (Eng. Detachment for special employment) in early 1942. This unit was somewhat bizarre as it had no official organizational structure. It had in its inventory a small group of three StuG III Ausf.D vehicles.
This unit was formed just prior to the Soviet invasions by order of Hitler himself. Its original plan was that once the Soviet lands in Europe were conquered, advances into hot climates such as Iraq were to proceed. Given that this never occurred, it was allocated for the North African campaign. These StuG III saw action during the Battle of Gazala and the Axis capture of Tobruk. At least one was captured by the Allies near Bir Hacheim in May 1942. Only one StuG III was reported operational by August 1942.


On Other Fronts
In the years following the invasion of the Soviet Union, the number of short barrel StuG III dwindled due to losses and being relocated for training units such as Sturmgeschütz Ersatz und Ausbildung Abteilung (Eng. replacement and training battalion). A number of StuG III Ausf.C and D survived almost up to the war’s end. For example, some were allocated to the training school stationed in Denmark in 1944. At least one StuG III Ausf.C or D was used by the Germans to fight the Czechoslovak resistance near the end of the war. One such vehicle was even taken out by the insurgents.




Modifications
Sturminfanteriegeschütz 33
For the need to fight the well-entrenched Soviet positions at Stalingrad, the Germans hastily modified some 24 StuG III vehicles for this role. The modification was simple, as the original StuG III superstructure was replaced with a new box-shaped one, armed with a 150 mm gun. Some StuG III Ausf.C and D chassis were reused during construction of the 24 rebuilt Sturminfanteriegeschütz 33 (English: assault infantry gun).

Remote Control Tank
Some Ausf.C and D training vehicles were modified as a Leitpanzer (English: control tank) to be used to remotely control via radio equipment and the small Landungsträger (English: demolition charge carrier).

Fahrschul Sturmgeschütz
An unknown number of StuG III Ausf.C and D were used as training vehicles. Their role was highly important, as an inexperienced and untrained crew had little combat potential on the battlefields. Some of these vehicles received long guns. At least one StuG III Ausf.C or D was armed with the long 7.5 cm L/48 gun. It appears to have been lost in combat in the later stages of the war.

Surviving Vehicles
Today, only a few StuG III Ausf.D vehicles are known to have survived. One can be seen at the Arsenalen Tank Museum in Sweden. Another one in running condition is located in the United States of America and is part of the DriveTanks association. This vehicle was actually one of the few operating in North Africa that was captured by the British. Lastly, one StuG III Ausf.D was used as a monument structure on Volokolamsk Highway near Moscow.



Conclusion
While offering a slight improvement in the overall design of the upper superstructure, the StuG III Ausf.C and D were in fact just introduced into service to help form new units and replenish lost vehicles. Like all StuG III vehicles, they performed excellently in their designated role. With the availability of a new shaped-charge round, their anti-tank performance greatly increased. Despite being built in rather limited numbers, they would remain in use up to the end of the war.



StuG III Ausf.C and D specifications |
|
Dimensions (L-W-H) | 5.38 x 2.92 m x1.95 m |
Total Weight | 20.7 tonnes |
Crew | 4 (Commander, Gunner, Loader, and Driver) |
Speed | 40 km/h, 20 km/h (cross-country) |
Range | 160 km, 100 km (cross-country) |
Armament | 7.5 cm L/24 |
Armor | 10-50 mm |
Engine | Maybach 120 TRM 265 hp @ 2,000 rpm |
Sources
- D. Doyle, (2005) German military Vehicles, Krause Publications.
- D. Nešić, (2008) Naoružanje Drugog Svetskog Rata-Nemačka, Beograd
- Walter J. Spielberger, (1993) Sturmgeschütz and its Variants, Schiffer Publishing Ltd.
- T.L. Jentz and H.L. Doyle, (1999) Panzer Tracts No.8 Sturmgeschütz
- T.L. Jentz and H.L. Doyle, (2006) Panzer Tracts No.3-2 Panzerkampfwagen III Ausf. E, F, G, H.
- P. Chamberlain and H. Doyle, (1978) Encyclopedia of German Tanks of World War Two – Revised Edition, Arms and Armor press.
- H. Scheibert, (1994) Panzer III, Schiffer Publishing
- Walter J. Spielberger, (2007) Panzer III and its Variants, Schiffer Publishing Ltd.
- B. Carruthers, (2012) Sturmgeschütze Armored Assault Guns, pen and Sword
- M. Healy, (2007) Panzerwaffe Volume two, Ian Allan
- T. Anderson, (2016) Sturmartillerie Spearhead Of the Infantry, Osprey Publishing
- T. Anderson, (2017) Sturmgeschütz Panzer, Panzerjäger, waffen-SS and Luftwaffe Units 1943-45, Osprey Publishing
- K. Sarrazin, (1991) Sturmgeschütz III The Short Gun Versions, Schiffer Publishing
- F. Gray, (2015) Post War Panzers German Weapons in Czech Service, Guideline Publications
One reply on “Gepanzerte Selbstfahrlafette für Sturmgeschütz 75 mm Kanone Ausführung C and D (Sturmgeschütz III Ausf.C and D)”
So the only reason for the Ausf D was essentially contractual?