Tried some Trail Boss loads with 200 gr Hornady's and was impressed with them as a fun plinking load. I don't think you can get into much trouble with it since it is very bulky and the pressures are low. With other powders you could get a double charge but not with Trail Boss. I believe a full case was something around 19 gr so a 9 ounce can goes a long way.
http://www.imrpowder.com/PDF/Trail-Boss-data.pdf
