The 55gr BK's were exceptionally accurate in my 22-250, but I was getting too many splashes on the surface with them on short range shots. On long range shots (200yds +) everything was DRT. So, I can't really give them a good recommendation for a coyote bullet, at least in a high velocity chambering like the 22-250 or faster. Out of a 223, they might be just fine. For varmints smaller than coyotes, they're tough to beat. But, I think they're just a little too lightly constructed, too frangible for reliable performance on coyotes, in my experience.
I've switched over to the Sierra 65gr SBT's and I think I've found nirvana. I think it's the perfect coyote bullet in the 22-250. Despite the warning on the box for twist rates of 8 or faster, they fly just fine out of my 12 twist Savage.