Panzer IV
…the recoil length was too great for the tank's turret, the recoil mechanism and chamber were shortened. This resulted in the 75-millimetre (2.95 in) KwK 40 L/43. When the new KwK 40 was loaded with the Pzgr. 39 armour-piercing shell, the new gun fired the AP shell at some 750 m/s (2,460 ft/s), a substantial…