Gun mantlet

A gun mantlet is an armour plate or shield attached to an armoured fighting vehicle's gun, protecting the opening through which the weapon's barrel projects from the hull or turret armour and, in many cases, ensuring the vulnerable warhead of a loaded shell does not protrude past the vehicle's armour. On many tanks during World War II, the gun mantlet covered both the main gun and any coaxial armament, and had the thickest armour on the vehicle.

Panther tank mantlet

Tiger I mantlet

M4 Sherman mantlet

Comet tank mantlet

T-70 cast mantlet

Leclerc mantlet

Leopard 2A4 mantlet

StuG III mantlet

A Jagdpanther mantlet

ISU-122 mantlet

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Wikipedia