It’s not a subject I know much about but the variety of feed systems used with machine guns has thrown up some design oddities over the years. No doubt it was thought that there was a good reason for them all, can we still see what that point was?
For starters, I commend you to the decidedly strange 20 round charger used by the Italians for loading their Breda machine guns. It would be interesting to see what other chargers. links, articulated sections, strips, hoppers and other products of inventive minds time and necessity have produced.
In anticipation, Peter