Not a gun writer for sure, but..........for what it's worth in regard to the throat diameters in newer 45 Colt Rugers. I have one of the newer Redhawks, (manufactured in early 2015) and have slugged the cylinder throats. My caliper says they are .452+. My tool only measures to thousandths, so .452+ means a hair over .452. Cast bullets run through a .451 sizing die shoot fine with virtually no leading.
