 The 76 mm was capable of knocking out a Panther at normal combat ranges from the flanks or rear, but could not overcome the glacis plate.Due to its 55 degree slope, the Panther's glacis had a line of sight thickness of with actual effectiveness being even greater.An M4 might only knock out a Panther frontally from point-blank range by aiming for its turret front and transverse-cylindrical shaped mantlet, the lower edge of which on most Panthers (especially the earlier Ausf.