Hi 88Mausporter,
I am an 62 year old Aussie who has shot since he was 10 and never ever heard of such a calibre. I also checked a book by the late Cyril Waterworth, called "Cartridges for Rifles, Pistols & Antique" and there is no reference that I could find that even came close. ?? good luck with your research, maybe there is such a cartridge but is so rare only a few exists.