Hi Englander,
Use the Lyman 429244 with 20.5 gr. BlueDot. It is one of the most accurate loads out of my .444 1-38" twist. I use that Lee310 gr. also with RX-7 or AA 2015. Real accurate but kicks like a mule. The Lee 200 gr. cowboy bullet shoots with 13 gr BlueDot. The Lee 215 gr. Flat-base with 14 gr. The Lee 240 gr is real good with 17.5 gr. (all BlueDot loads).
Hope this helps,
Newtire