Best load with a ball is 20 gr and the rest a filler, Cream of Wheat or cornmeal.
I use 41 gr of Swiss FFFG and with a boolit I top at around 32-35 gr but don't know the velocity. Very close to a .45.
Pete has the Rem buffalo hunter and he has taken many deer with it, he gets over 1100 fps and it seems to be more accurate then my ROA with the hot load. I don't know the twist.
But back to the .45 BH, the 1 in 16" twist is very forgiving over a wide range of boolits. 250 to 335.
A great deer boolit is the Lee C452-300-RF.
Another good one is the Lee 452-255-RF.
I made a mold for the ROA that shoots well and my friends also love it in the 1911's. I also have the Lee .456-220-1R.