Pretty much any front torso hit from a varmint bullet out of a 22-250 will turn them off like a switch. Same thing goes with a 243. Until you really get way out there. Sometimes even a mid to close range shot with a 223 and they don't turn off immediately. You can see the difference after hitting a bunch of them with each caliber. I will still use a 223 if I know the setup is for close range, or if I'm near a farmhouse, etc (noise), but I prefer either the 22-250, or the 243 if it's windy.
I like the Hornady Vmax bullets myself. They come in 250 count bulk boxes, and I use the 50 gr for 223 and 22-250, and the 87 gr for the 243. I also use these same loads and rigs for prairie dog shooting (reason I like the 250 ct boxes). I did pole axe one with my 6.5-284 one year out on the prairie dog fields. I had just made a shot on a prairie dog at 1K, and left the rifle sitting on the rest to get a drink. Came back and saw something moving around, looked through my scope and there was a 'yote out there scarfing up the dead bean bears. I just had to jack in another round and nudge the rifle over a hair, and "bang". Dead 'yote. Pretty funny.