Even with two hits, you say you missed the 2nd shot, it doesn't surprise me a bit that he ran off when the range was over 150 yards. Heck, I've seen prairie dogs hit at that range with my .17 hmr make it back to thier holes! Just not alot of energy left for that tiny bullet to quickly dispatch a coyote. He'll probably die from the first shot if it made it into the lungs, so I wouldn't worry about not finding it. They can go along ways with a lung hit from a center fire rifle sometimes.