I am a lifelong machinist/mechanic and the first time I encountered military brass w/crimped primers the first thing I thought about was a countersink, simple, effective, inexpensive, and just plain old works. Since then (1990) I have used a countersink to quickly remove any crimp, plus I have "repaired" some brass (S&B primer pockets had no/very little chamfer on pocket mouths, and chamfering .44 Magnum brass stopped Lee Loader priming "POPS!"). https://www.mcmaster.com/#countersinks/=15es1qx