spent casing marking

Question
found a spent casing while doing a live fire exercise on a canadian forces range with the markings DA and 68 on it, looked bigger than a standard NATO 7.62mm, any ideas what it might be?  the brass looked very old, maybe a .303?

Answer
Hi Ken,

This is a pretty easy question to answer...you provided several clues in your question.  The head stamp markings on military ammo are different than civilian.  Civilian ammo will usually carry a code for the manufacturer and the caliber.  Military ammo will usually identify the source of the ammo and the year of its manufacture.

The "DA" is for Dominion Arsenal in Quebec.  The 68 is most likely 1968, or the year the cartridge was made.  

If I had to take a guess, I'd say it was probably a 7.62 since according to records, Dominion Arsenal quit making .303 British in 1958 and stopped producing .30-06 about the same time.  Mostly all they produce in recent years was 7.62x51mm, 9mm and a little .50 BMG.

Hope this helps you out...

Doug Little