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I am not sure what the policies are now, but back a few years ago, some of the Salvage Dealers in Lethbridge, Alberta, had all kinds of stuff that was picked up on the range and sold as scrap.
To name a few, fired 81mm Mortar Heavy and Light Illumination rounds, 2.75 inch Rocket Casings including some that were originally loaded with Fleshettes, 7.62x51 and .50 Browning brass by the bagfull, and 2 inch Mortar Illumination rounds. I have seen pallets of Small Arms Ammunition steel boxes, and up to 30mm steel boxes, and you can buy them at the local Princess Auto Store almost any time.
At a scrap dealers, I have bought 25 pounder solid Anti-Tank projectiles picked up on the ranges and sold as scrap, and one dealer in Lethbridge even had a cut up barrel from the HARP Project.
I am still using 1976 IVI produced 7.62x51 brass that I bought by the burlap bag full at 27 cents a pound.
As far as parts and other things go, I even found C1 Safety Sears and Springs in an Edmonton surplus store. The owner had bid on a "lot" and two boxes of these were in that Lot, along with other things.
Almost any Gun Show in the United States had this stuff for sale. Not sure what the regulations are now, or what Homeland Security and Canadian Customs thinks about it now, but a few years ago, you could buy it easily.
However, I do agree that if you are in the Service, and you pick up and keep even one fired brass casing from the range, you will be in a world of hurt if found out. Remember the line up after firing on the range, and policing up the brass. "Sir, I have no live rounds or empty casings" was a standard declaration.
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