I killed a lot of coyotes in Az with a 22 mag. 40g Winchester is a great pick. Plastic tip bullets do not penetrate well, break bones, and bleed off velocity very fast. Plastic tips work best on jack rabbits.
You can hit a coyote in the lungs and he may drop, or run like a scalded cat, short range of 75 yards and better gives best results, but I have dropped them at 125 because I spent a lot of time with my rifle.
Some bullets just do not kill worth a darn, especially as the range gets close to 100, and the Win HP works well. One thing for sure, if their tail is moving after the shot, shoot them again. I have really enjoyed my Ruger all weather 22 Mag, Marlin tube feed, and Marlin 25M. I had a Mauser 210 that handled like a true big game rifle, still have some extra mags for it.
Foxes can be hard to kill, not much to shoot at, hit them solid on the shoulder if you can. CCI's leaded my barrels up, so I avoid them like the plague. The 40g Win HP is a true jacketed bullet, not a copper plated lead bullet which you would be wise to avoid at all costs.
