'Boo, I'm no physics major but I do wonder how the force required to squeeze such thin brass back to size can be greater than the force required to strip the threads off a properly adjusted die. Logic dictates that either your set-up was wrong or the die was "modified" FWIW an old tradesman once told me "a bad worker always blames his tools" L.C. dies work very well for me in 30-06, 7 R.M. and 375 H&H, but hey mebbe I'm jest lucky.
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