The load data that here does not show more than 1332 or so. And that is the ball park of the Buffalo Bore loads as well as others
http://www.realguns.com/loads/460Rowland.htm Your peak pressure at 1450 fps is well above the 38,000 psi for the cartridge and is not a load that I want to be standing near when fired. Metal attitude gives no warning before it lets go.
38,000 psi is above the recommended pressure for the 45 Colt in a Ruger only recommended loads and not something that I want in a semi auto. You are living on the ragged edge with a 1450 fps load, enough 38,000 psi is more than I am willing to stand behind in a semi auto recoil activated lock up system. That pressure would not concern me in the auto mag.
