So you got a thousand of the critters.
So what?
Pulling it down and handloading the charges into fresh brass, it gives you enough powder to load 1,000 rounds of MilSpec shooting ammo. That would cost about $200 to buy at a sporting-goods shop.
And it gives you 1,000 good bullets. Cheapest 8mm slugs available right now (that I know of) are 32 bucks a hundred, so you have 300 bucks' worth of good bullets.
You haven't lost any $$$ and so the order is simple: Thou Shalt Not Kick Thine Own Fundament Without Good Reason.
Just get some fresh brass and primers and change the loads over to the new cases. Much safer, problem gone.
What you have are classic "shoot-throughs". Generally they show up first at the neck or the shoulder. Some of yours are far enough back that they could get nasty, so my advice is just to use better brass, switch your loads over...... and have fun.
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BTW, who the heck is DOMINION ARMS? Never heard of them. If you mean Canadian .303 ammo with a DA headstamp, that is DOMINION ARSENALS, the Government ammo plant of the time. They made all that 'orrible .303 ammo with the big copper Berdan primers which were corrosive AND mercuric: wreck your rifle and your brass at the same time. They are loaded with Cordite MDT 5-2, which burns considerably hotter than most modern propellants, although much cooler than Cordite Mark I. DI ammo is Defence Industries, a WW2 Crown Corporation staffed with huge numbers of people, but the key staff were from the Dominion Cartridge Company. They made beautiful .303 ammo from 1941 through 1945 with noncorrosive, nonmercuric Boxer primers which likely will stand forever as the best .303 military ammo ever turned out. It is also FINE reloading brass. It is a bit long in the tooth now, but small miracles may be worked with a sinkful of cold water and a propane torch. My couple of dozen .303s all love the stuff.
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