I started out using my Browning bolt-action .243 Rifle,it works great in calm to windy conditions,my next choice for knock-down power and affordability in ammo would be a .223 Rifle.
My choice I went with was the CZ-USA "Varmint" in a .204 Ruger...talk about a long range Rifle that is very accurate and it has taken down every Coyote I have hit with it.I'm using Winchester 32 grain ballistic-tip bullets but plan on going with the Sierra Blitz Kings in 39 grain becasue of better accuracy.I'm completely thrilled with the .204 Bolt-action Rifle,can't say enough praise about it!The shells range from around $16.00 to $25.00 range per box of 20 shells depending on the brand and when they are on sale.