Im not 100% shure it actually can turn 360°, because that Mk 103 is mounted as a “Baumaffe”
It is, a simple pivot mount with free traverse, and to turn to the other side would mean the gunner would have to move around the axis of the gun.
Here an example mounted on a simple wooden block. (They also existed on full metal podests.)
Or that the angles dont line up.
Or that it is half floating.
Or that the cutting was so bad that there is even still some of the engine deck of the T-34.
XD I’ve only ever seen those on Hogan’s Heroes, and I always assumed they were just a prop made to look something like a tank for the average audience. It looks like a frightening mix of a Sherman and a Nashorn.