Haenel Magazine Design

[Vlim]

The straight cut helps to leave enough material to pin the base to the tube through the center of the button. Also it is cut at a straight 90 degree angle, so easier to manufacture.

Since the magazine was introduced and designed well before WW2, the war itself played no role in the design.

Apart from that it works. Functionality and cost price was probably more important than looks in those days.