Can anyone clue me in on the meaning of a .50 BMG projo with a black tip and red ring. It's on an case hstp'd "IVI" over "73" (Both oreintatied the same way). that has traces of a green primer annulus. ANy reference I can find to those projo colors, seems to list these as French AP-T but:IVI i Canadain and as far as I am aware, Canada used UK marking convention during WW2 and then NATO markings after that. Neither of those color convetions used those colors that (I'm aware of).
So any help?