Re: Case separation ??
Set up your dies to push the shoulder back .001" or less. Essentially, ignore the belt. The article that Coach linked to is spot on. One minor detail that is easily missed in that article is "consistent application of sizing lube is important." I use Imperial sizing wax, I apply it with my fingers and have not found a more consistent lube, when you're reloading for accuracy.
If some is good and more is better, then too much is just right.
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