TC Contender in .204 Ruger
I've had success using most of the guns in my arsenal for coyotes with the following results:
.17 Savage - Nice for close work but too light for a large dog much over 75 yards; It's hard to follow a blood trail from a hit 'yote through the brush when grounds frozen but there is not snow to help with the sign.
.270 Winchester - Hand loaded to match volocity with my dear/elk round. Does the job but makes a mess and any range I am capable of shooting accurately, about 250 yards.
30/30 Marlin - The best of the three except shots at 200 yards begin to requrie some hold over which is OK since for the me the challenge and fun is calling them in close rather than the shooting.
When a dedicated coyote gun makes it to the top of my list I'm planning on making it a TC Contender rifle in .204 Ruger. It should be enough for coyotes but hopefully not too heavy to make a major mess of a fox or bob cat. The single shot is because I know myself well enough to realize that if I had an easy backup shot, say from an AR, I wouldn't take as much care with the first shot and would end up with more misses. As I said the challenge for me in coyote hunting is calling them in close. The shooting is a cross between a public service and practice for big game hunting.