I use 46 grains of varget, 155 gr. HPBT Palma MatchKing, 2.80" OAL.
Shoots 1/3 - 1/2 MOA all day in my remington.
As always, start low with powder charge. I started at 44.5 grains and slowly worked up. Found 46 worked best with the 155 SMKs.
Also, my rifle just wouldn't shoot the 168 SMKs. I tried and tried. It must be cursed. It loves the 155s though.