[Ron Wood]

I would tend to go along with Pat, a soldier would not attempt to reload a Trommel during a battle. In fact, unless there was a significant lull in the action, I doubt that any magazine, Trommel or regular, was reloaded while bullets were flying. You just swapped magazines and kept on going (but not disposing of the empty mag), until it got down to hand-to-hand. Also, I believe that a soldier, particularly Stosstruppen, would carry more than one TM.

Considering the time and effort required to load a Trommel, I think Pat is correct that the unit armorer loaded them, hence only one loading tool per P-Kasten.