Cat is right on on the Blitz, not to be confused with the blitz kings.
Blitz kings are the most explosive out there, so I avoid them on coyotes.
Of the Sierra 55's, the SPT BT, 55g BTHP, 55 Flat Base have all done very well on coyotes for me at velocites from 4150-4100 fps.
I did have the 60g HP shoot holes straight through several coyotes in a 1-14 twist at 3450 fps, so I put that bullet on the tough side. Faster twists should help the 60g HP bullet open up faster.
The Sierra 50g Spt is also a great bullet for coyotes and they did not blow up at 4150 fps on coyote shoulders.