I have a cartridge that I believe is a 11mm Gras. I have the book “Cartridges of the Gras System” by Mention & Ramio. The headstamp “O/1/82/Mx/ is shown on page 7 but does not identify who the “O” is. I think the “Mx” is
"Atelier de Fabrication d’Issy-les-Moulineaux” who is the metal supplier.
Also, I do not find the round nosed brass FMJ bullet as a load type for 11mm Gras. in any of my references. So, is this a 11mm Gras or something out. The headstmp says “Yes” and the diminisions say “Yes”, but what model of 11mm Gras is it.