You're talking military brass here:
1. Deprime the cases. After much experience, I use the cheap Lee depriming tool with a hammer. I found the RCBS Universal Depriming die to be unserviceable, after too many broken pins and bent spindles.
2. Remove the crimp from the primer pocket. There are a number of tools for doing this. I have the RCBS Primer Pocket Swaging Tool, and it works....to a degree. I don't believe it leaves sufficient radius on the primer pocket, so I also give the pocket a whirl with my chamfering reamer.
3. Clean the cases according to your regimen of choice...lots of thread in lots of forums on this subject. For normal brass that's just dull, with no heavy tarnish, I just use the vibratory tumblers with corncob media and NuFinish auto polish. When the tarnish gets heavy, I've used white vinegar & water, and I'm about to try Lemi-Shine.
4. Now you're ready to load!
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