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Another problem D-early G model Panther’s had was the shot trap caused by the rounded gun shield. Shot traps would often deflect projectiles downward into the weaker super-structure of the vehicle, injuring the crew if not outright killing them and disabling the vehicle. Late production G’s corrected this problem by introducing the “chin” mantlet. Had the war continued, Panther tanks and later E-50 vehicles would have had Schmalturm or Schmalturm type turrets with a completely flat turret face. 

In modern tanks shot traps presented by turret armor are largely irrelevant because modern ammunition has such a high muzzle velocity. Modern AP rounds (APFSDS) will either partially penetrate or shatter on impact due to the angle of the turret armor. 

Взято: ostrich-san.livejournal.com