I'd go with a 255-260 cast SWC, also. The loads mentioned are good ones, but let me throw in yet another. This one's the favorite load of Hank Williams Jr (a noted single-action and 45 Colt expert): a magnum primer and 20-22 grains of 4227, held in with a firm crimp. There's no chance of a double charge, it doesn't have the ear-splitting blast of 296/110 and it launches at 950 to 1000 fps. Very nice load, although you may see some unburnt kernels.
