http://militarycartridges.nl/uk/9mm.htm
Canadian manufacture.. my guess is non corrosive
any more knowledgeable (ww2 vets? ) people pls chime in
DI: Defence Industry Ltd. Verdun (Québec).
43: year of manufacture.
9 mm calibre cartridge.
DI==Defence Industries...a company completely different and independent from either the Dominion Arsenals ( Govt.) organisation, or the Dominion-CIL private contractor. Set up with assistance from the fore mentioned in 1941-2 to manufacture BOXER primed ammo ( .303, 7.9mm, 9x19mm and possibly .380 and .455 Revolver ammo.. 30 cal is also a possibility...
Production Terminated 1945, but it is surmised the plant was "resurrected" ( either in situ or elsewhere) to make "Covert" ammo (The "MM" series) after WW II...the jury is still out on the dating...Maybe Wikileaks will find some old CIA docs somewhere???
http://forums.gunboards.com/showthread.php?152032-Canadian-quot-MM-quot-Headstamps :
"...The pilot lot of 9mm Para ever made by Dominion Cartridge was headstamped DC 42. With acceptance, the headstamp was changed to DI 42, reflecting the establishment of Defence Industries Ltd. That information from my now-departed friend Jim Houlden, who set up DI, and who kindly provided me with a sample of the trial DC 42 ball ammo, and several different try dummies. Further in 9mm the sequence of magnetic bullets is correct if you add about 10 years to the dates, and the black primer seal becomes correct, as in the 50s, Canadian 9mm had a black seal and not the purple seal they had in the 1940s.
Also, after Dunkirk, there was a plea from England sent out to their colonies asking for help in the emergency development of a non-corrosive 9mm cartridge.
I think this went out in 1941 or 1942 - Lew Curtis knows. He saw the declassified document. I find it hard to believe that would have been necessary had Canada already been in full production of non-corrosive 9mm ammo for a year or more...."