The gunner (seated underneath the machine guns) operated the JM Reibel by means of his feet and hands. His feet operated two pedals which controlled the rotation (electric drive) of the turret. Right in front of him was a wheel with which he changed the elevation of the guns and which had a trigger for the machine gun on the left. In case the electricity was cut, a second wheel was at his disposal, with a handle that also served as a trigger (bowden cable mechanism) for the machine gun on the right. Needless to say that it must have been a very noisy place to work in with it’s metal wall and roof...
During an attack at night, visibility was close to zero for the gunner in the turret.
Therefore, an ingenious solution was thought up for automatic fire.
A construction was made that consisted out of a graduated arc, with a constantly changing profile, that ‘followed’ the contours of the surrounding terrain. Because of this arc, when the turret was rotated, the elevation of the machine guns was adjusted, so that barrage fire was laid down around 20cm above the barbed wire belts at any time during it’s rotation.
A single person on the intermediate level was responsible for the supply of camemberts (nickname for the magazines) to
the top of the turret. This task was accomplished by a hoist. Empty magazines were transported back from the firing
chamber to the lower level.
Here, three soldiers had the task to empty the ventilated box in which the fired cases were collected, reload the empty magazines, and make sure the whole machine operated trouble free.
Later on during the building of the Maginot Line, one realised that the importance of armoured warfare could not be underestimated,
and the MG turrets lacked the ability to destroy tanks.
So a labour intensive plan was devised to equip them with
a 25mm gun that was combined with two MAC 31's (alternative AM combination).
The plan was to drill a new embrasure for the right hand machine gun, because it’s original position was taken up by the anti-tank gun. Fourteen turrets eventually got converted, while others were in the process/ on the list of being re-equipped. Needless to say that during this process, it was not possible to use the turret.