German MG151/20mm Wooden Dummy?

The attached pictures show what I think is a wooden MG 151/20mm dummy in a clip which I have just acquired. I have shown it along side a MG 15/20mm case (missing it lacquer) for comparison. My question is, could this be a legitimate dummy produced during the war or is it something someone has turned up on a lathe?

Thanks in advance.

Ian
IMG_2907 IMG_2908 IMG_2909

Sure nothing official as it would not work when being cycled in a gun.
Maybe something improvised for a display.