I dont load for the 300 wby mag but i do load for 300 win mag. I dont have any loads to give you as a starter but i will say this anybody could give you a load to start with that may have done good in their rifle but wont neccisarilly do well in yours just keep that in mind. As for bullet choice I really would go with atleast a 180 grain TSX from my experience the lighter bullets dont do well in my 300 win mag its seems to prefer the 180 grain or heavier id imagine it would go the same for a 300 wby mag if you havent bought powder yet or have some H4350 around you might give it a shot I have had the best consistancy with it in my 300 win mag. good luck