Look into 45 Super
The 460 Rowland is kind of a long walk to get somewhere when you can do almost the same thing with the much simpler 45 Super, which is thick walled 45 ACP brass that you can shoot in a 45 ACP with beefed up springs. Check out the Ace Custom 45 website for details, but the "unofficial" factory spec is a 230 grain bullet at 1200 FPS, which I can achieve with my Springfield V-16 longslide. The V-16 comes with a 45 ACP and a 45 Super spring, and you just interchange the two.
I have also worked up an EAA 45 WF to 45 Super, and with a 4.4" barrel I can get a Hornady 185 XTP to come out the front at 1250 FPS. That essentially makes the gun a 10+1 41 magnum automatic, except that the bullets are 45 caliber.
