Right now it's the 300 gr .451 Nosler Partition with the supplied sabot, 110 gr T7 2f, Win 209 Primer. Extremely accurate in my Omega @ 100yd and 6 inch groups at 200 with lots of thump there (over 1000 ft lb @ 200).

However I have some 300 gr .458 45/70Nosler Partitionswith MMP Orange sabots waiting in the wings for testing.