There are essentially 3 different load
"tiers" for the 45 Colt.
It depends on what gun you have??
There are the basic old light loads, medium loads and Ruger only loads.
So it all depends on what you are shooting and how heavy a load you want.
There are gobs of information-out there on these loads.
If you must use Trail Boss (It smells like Cowboy Farts) here is a reduced formula that can be used for anything.
http://www.imrpowder.com/PDF/Trail-Boss-data.pdf