I always shot Seirra 100gr SBT, the same bullet that federal loads in their premium loads. It works great on deer and due to its tougher construction isn't too destructive to coyotes or fox if you shoot them farther back and avoid the shoulder and hip bones. I have heard great and horrible things about the 55gr bt bullets in the 243. One guy that I talked to said they were great and that in three coyotes he has gotten no exit holes and instantly dead coyotes, another guy I talked to said that he goes about 50/50 for no exit wounds on coyote with the other %50 being blown up pretty bad and that it will just about seperate the north end of a fox from the south end of a fox. I always shot the same bullet out of my browning .243 because I was so pleased with its accuracy and perfromance on deer that I never shot any of the lighter bullets out of it, now that I live in alaska I am sticking to the 100gr bullets on the off chance I might encounter a wolf.