While still fighting in Poland in September 1939, the German High Command looked ahead to the coming battle with France and ordered a vehicle for use against the fortifications of the Maginot Line. In response Krupp set about designing a self-propelled 10.5cm K18 long-range gun based on a Panzer IV tank chassis.
The new vehicle’s rotund profile quickly gained it the nickname ‘Dicker Max’ (‘Fat Max’). On 31 March 1941 Krupp-Gruson presented the first of two prototypes designated 10.5cm K18 auf Panzer Selbstfahrlafette IVa (10.5cm K18 on Armored Self-propelled Mount IVa) to Hitler.
With France defeated, Hitler ordered that this vehicle be developed into a heavy Panzerjager (tank-hunter) capable of destroying the anticipated British and Soviet super-heavy tanks. Production of the 10.5cm K18 auf Panzer Selbstfahrlafette IVa was planned to start in spring 1942, but was cancelled in favor of other vehicles.
Hypothetical Combat Service
The two prototypes were assigned to 521. Schwere Panzerjagerabteilung for a planned attack on Gibraltar. When this was cancelled, they were assigned to 3. Panzer division for Operation Barbarossa. One of them was lost in an ammunition explosion and the other returned to the factory in October 1941 after three months in combat.
Having proved itself very effective against Soviet KV-1, KV-2 and T-34 tanks, the surviving Dicker Max returned to 3. Panzer division alongside the even better-armed Sturer Emil in 1942.
Meanwhile, the success of the two prototypes led to the Dicker Max being put back into production in the middle of 1942.
Dicker Max is first and foremost a gun-carrier and the gun it carried was the long-range Rheinmetall s 10.5cm K18 artillery piece fitted with a muzzle break. This gun weapon can penetrate 111mm of armor at a 30 degree slope at 2000 meters, 30% more than the famous 8.8cm FlaK18 anti-aircraft gun! Such a slow gun is usually rather slow-firing, but with two loaders and ammunition ready to hand, it gives a good account of itself.
In Flames Of War
The powerful 10.5cm gun mounted in the Dicker Max is more than capable of destroying anything but the heaviest super tank.
Dicker Max is best used as a long-range tank-hunter firing from concealed positions behind your own troops. This will keep the enemy at a safe range where it cannot penetrate the relatively thin armor of the Dicker Max, while allowing its powerful long-range gun to pick them off.