Mike H U F F has extensive experience using all kinds of rounds on predators... I know he doesn't like the 17's for coyotes... I know many of the men out West and Mike are now using the 243 for coyotes... I have a 243 and a 6MM but just use them for deer..However I'm going to start to use my 6.5 BRM Encore .264 Cal for chucks and coyotes using the 140 grain Hornady bullets. I really like how accurate that EABCO caliber shoots..As you know that uses a 30/30 case and a .264 bullet.