No love for the 243?the problem I have is this.. I would never use a .224" diameter slug on a white tail or any deer. the smallest caliber/diameter I would use is a .257". as in 25 WSSM or 257 Rob.
now for the most devastating .224" out of a 223 rem or a 5.56 it has to be the 70 grain Barnes TSX. that is with a 150 yard max range as you said.