I previously posted about some dodgy quality armour the British found in PzIII tanks. Samples obtained from various tanks tended to behave in a similar fashion, but other trials showed that this performance was not exclusive to just one type of German medium tank. The performance of the PzIV's armour against the British 2-pounder was so disappointing, that the British theorized the Germans are saving all of their high quality plate for prospective heavy tanks.
"Firing trials by a 2 Pdr. gun mounted in a Mark IVA Cruiser tank have recently been carried out against a captured German PZKW IV 22 ton tank in the Middle East.
The armour basis of the German tank is:
- Turret:
- Front: 30 mm (1.181 inches)
- Side: 20 mm (.787 inches)
- Hull:
- Front superstructure: 60 mm (2.362 inches)
- Rear: 40 mm (1.57 inches)
- Side Centre plates: 40 mm (1.574 inches)
- End plates: 20 mm (.787 inches)
- Tank engaged broadside at 500 yards. All shots on turret and hull side armour penetrated, passing completely through the tank and also penetrating far side.
- Tank engaged head on at 500 yards. All shots penetrated. 3 shots broke up inside tank. 3 shots passed through tank and penetrated 20 mm armour on far side.
- Tank engaged broadside at 700 yards. Results as for (a).
- Tank engaged head on at 700 yards. All shots penetrated and broke up on far side after penetrating 10 to 15 mm.
- Tank engaged broadside at 1100 yards. All shots penetrated.
- Tank engaged head on at 1100 yards. All shots penetrated.
- Tank engaged head on at 500 yards. 6 rounds fired at thick single and double armour. All penetrated, except one.
Comment: As a result of these trials, 500 yards is considered the maximum effective range against the thickest frontal armour on this mark of tank. The results of these trials are satisfactory confirmation of the penetrative effect of the 2 pounder.
During the winter months the Germans have undoubtedly been making extensive trials with captured British 2-pdr A.Tk. guns and as a result the vulnerable parts on the tanks have been increased by extra plates being welded or bolted on. See summary 3, reference 1/A/(i)-(v). The Germans apparently considered that their tanks had thus been rendered immune to our 2-pdr. In France, the 2-pdr was used with shell and not shot. Against 2-pdr shell the German tanks may be immune, but as these trials show they are easily penetrated by 2-pdr shot at all reasonable ranges. It is hoped that the full details of German armour plate will be available shortly. It is of the machineable type and therefore easy to produce, but does not appear to be of high quality. It must be borne in mind that the heavier types of tank may be made from a superior quality of plate."
AFV Technical Intelligence Summary No.4, June 1941, 1/RAC TECH/1(SD) Canadian Military Headquarters, London (CMHQ)