I have written a short article on the Ethiopian .30-06, 7.62 × 51 mm & 7.92 × 57 mm ammunition that is becoming more prevalent on the US market at the moment.
Still a few leads to chase down, and we have a researcher in Ethiopia looking into the history. As you might expect, it has been a little difficult to confirm some details. My thanks to the IAA members who have helped! I would certainly be interested in any further information you may have.