my farthest confirmed kill on a coyote today. 612yds with a 223, no range compensating reticles, no target knobs, just old fashioned kentucky windage. i have now killed dogs at 612yds, 582yds, 498yds, and a whole pile between 275 and 325.
223 doesnt have much power at that range, but this sleeping dog got up and ran only about 70yds before falling over dead.