The. 460 Rowland is a hoot and a half. Had one but sold it. Sigh
If you do build one, make sure you give your loads a hard crimp due to recoil set back.
my 454= 300gr XTP Magnum @ 1500fps. It showed zero pressure signs and still below book max charge. I stopped because it was lazer accurate and the SD & es #s were very good.