After trying both Nosler and Barnes 286s with 66 grains of Big Game I settled on the Nosler because it was more accurate and the TSX got significantly less velocity than the Partition with the same powder charge. My 20.5 barrel was only getting 2300 with the barnes and slightly over 2400 with the nosler.
I see you're using CCI 250 magnum primers. I'd recommend trying the 200 large rifle. I tried both and found better acccuracy and consistency with the CCI 200.
I'll have to go dig through my notes regarding the COL of the barnes load, but I can tell you the partitions are seated so the groove on the bullet is right at the case mouth.
You seem to have excellent english so I'd recommend getting some John Barsness (Mule Deer here on the fire) books. There's some good 9.3x62 info to be had.
