I live in Saskatchewan, coyote hunting is and hopefully forever will be our pass time. With this, I've had many years in searching for "the perfect coyote gun" and sad to say, I have never found one. The idea is this. 10 yards to 500 yards, 1 shot, only an entrance and no exit. Well, that's a lot easier said then done. What I found is this, re 223 and 22-250 are great for killing, especially the 22-250 and at distance, but exits can and not at are messy. I started wth a 22-250, shooting every bullet you can think of and always had a number that exit. So I went down to a 222, with 20% less energy, at close range a it's bad, but at distance it's great. I then got a 204, same thing, at distance it's alright, up close its terrible. So I went to w 17 fireball. Now out to 200 yards your great, no exit, kills them mostly and a great all around caliber. HOWEVER, wind throws that and the 204 like crazy. So I got a 22 hornet to add to the collection. Well, let me tell you, no exit, kills them, incredibly fun round BUT you're limited to 150 yards. So ultimately it boils down to this. Hollow points, going at a moderate speed, shooting a a medium weight bullet. Anything with a ballistic tip go far, far away from them. Use a temperature stable powder and for the love of god don't shoot FMJs. They are cruel bullets and don't kill. Now I'm saying this because, I'm that guy who skins coyotes and has to sit down with a needle and thread after. NOT the guy out killing them (as much as you are). Any exit larger then a toonie will stretch out to be much larger then a Skoal can by the time he's ready to be put on the board. Essentially, to have a perfect coyote hunt, you need to bring a 12 gauge, 22 hornet, 222 and then a 6mm/243. Then depending on the distance you pick your gun, but we all know that's not possible. I hunt with the Predator Quest guy from Sask and he shoots a 22-250 with 50gr vmax. BUT he does a lot of needle and thread work.
