Perhaps he already has a can, and wants to keep it quiet as possible!?!? Why, why, why does a group like this, who apparently loves to experiment and learn new things about all things BANG, make such derogatory comments to a fellow asking a simple question? I think valid, EXPERIENCED comments are proper here (and there are a number of them above), and the snide stuff can stay in your heads. It does sound like from those experienced at such things like a subsonic 223 is not necessarily a consistent killer of coyotes? And possible tough to get as an accurate-enough load, even for short range coyotes? I would think an accurate enough load with, say, a 75 gr Amax or some such would be a penetrating, killing lungs/heart load, but almost def not a bang/flop load, on coyotes.