Howard, I've flown these cast bullets in my BC with success:
* ... Lyman 457123 - 535gr
* ... Lyman 457661 - is the Dixie Bore Rider - 510gr
* ... DD/PRS 500gr Twin Groove-Version 1 - 500gr
The 2nd version of the DD/PRS custom mold will be out in the Spring and it is based on a Postell design.
All these bullets were shot with Goex, Swiss, H777, IMR5744 and H4895 with decent groups out to 600 yards. Grouped a 6.8MOA @600yds this Summer using the Twin Groove over H777