Would depend on the terrain and the range of the closest/farthest shot.
Already have an AR? The AR (.223/5.56) is a good coyote round with quiet a bit of distance. The semi-auto and mag capacity also allows for quick follow up shots.
flat terrain with maybe a 2-300 yard setup. Asking because I do not know, but what would have that good front shoulder knock down power at that yardage with a smaller cartridge. What is a 6.5 creedmoor compaired to a .243.
I have whacked them with several different kinds of guns.
Open country 2-3 hundred yards I would go 22-250 or possibly check into 204 Ruger. That's what I would recommend if you are saving pelts. If not Blas away with what you already have. As others have mentioned 223 is also a nice choice. With today's projectiles it can reach out. All depends on if your a handloading guy.
I used a 222 for years and my shots were all under 150 yards. It did great for calling yotes and fox kills.
I was given a nice 22-250 by my neighbor for killing so many yotes and ground hogs. Good caliber but a bit more than I needed.
I bought my first .243 in '89 and haven't looked back. It's my favorite caliber for any game or varmit local to us around here.
That being said... I keep an AR at the doors just for yotes and bad persons.
The cost of shooting AR rounds is cheap. I like that.
My 243 has killed many coyote, but dang, it blows a hole in them. Never a run off with it either. It'll cut a Fox in two. The only reason I switched to 204 is for possible Fox encounters. If I'm in an area where I never see Fox or an area where the hogs lurk, then I'm launching 80 grains of destruction out of the 243.
We've had the same experience with the .223 but it may be partially due to the ammo he is using. The polymer tipped varmint ammo cuts the yotes in two and really tears them up.
I dunno. I like Two Four Three pretty well. I don't care about giant holes, so I load the 85 GameKing to "hot and fast" and go forth to demultiply.
For their size, it's like using a belted magnum on deer: hitting a coyote just about anywhere in the
chest cavity with it is going to end up as a DRT.
I chose the bullet and cartridge carefully so that it would be the right mix of power and portability for just about any animal in this state. I put it together long before rifles were legal for deer, but did so in observance of the 6mm rule in almost all other states.
I can verify that a lowly little 18" featherweight .243 will put the hammer of Thor down on any dog or deer sized animal it hits if you can do even a decent job on shot placement.
But then, .22 WMR can also DRT...they don't like .50 smokeless very well, a .223 will quite soundly anchor them,...
Truthfully, I probably like .243 for coyote so much because it is an over-engineered solution. I like safety margin.
And yes. The Creed is about a 1,200 yard coyote rifle in a longer barrel.
For coyote fun snacks, I'd load up some 107 MatchKings and just see what happens...it's really a rhetorical question with a legitimate elk cartridge in the pipe.