It might be worthwhile to mention, once more, case head separations are caused by excessive head clearance; not by changing primers or by properly sized barrels. By the way, I've worked with a bunch of older Rugers and none had a .003" oversized barrel. Modify case sizing procedures and separations will cease.
There is an exception; in a rifle with rear locking lugs, case stretching occurs to a greater extent at higher pressures. GD
