Yesterday evening I drilled a piece of steel to safely hold the 223 brass and ground an Allen wrench like Possomcops suggestion. I had to reshape it several times during the operation. The results is that about half the primer sleeves were easy to remove. About 1/4th more were removed with some difficulty and the rest were just too tight to budge. Many of these had been found while attempting to swage the pockets and the ring had been compressed. It appears that all of them had significant tarnish and the pockets were really dark after the primer remains finally gave way.
There were HS of all kinds and no brand showed up important out of the represented group. It appears they were simply badly tarnished range brass that had severly weathered or been improperly stored. The Mil brass dated from 80 to O9 so it may have weathered for many years under adverse range conditions. None had green spots or pits, and citric acid with SS pins cleaned even the pockets to bright brass with a normal time tumbling. I also found half a doz. that were dark brown that the acid didn't touch. They were not magnetic???
Being retired and welcoming a sit-down task, the brass I saved was worth the effort, but those without spare time might understandably forget it. I saved a #10 food can almost full of mostly X1 Mil brass which is my choice to reload.
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