There are two powders and one bullet I would recommend. Use a 200gr SWC, the Hensley & Gibbs pattern has worked best for Me. Use either- Clays, start with 3.7 and work up till you get the velocity floor your'e looking for- about 650fps=130 so, 685 to 700 is what you want. With bullseye, start with 3.6 and work up to 4.0. With my moulds (Lee 200gr SWC) I find that 3.6 gives about 685fps from my 5" Springfield Armory match gun, but accruacy is best at 3.9 (what my measure throws). This should give you an accurate and economical load ( so you can practice/shoot a lot !).
Good Luck !!
"There is no such thing as a second place winner in a gunfight" Bill Jordan