You have probly seen some of my post on the .22-6mm also known as the .224 TTH. I love it and it seem to be a fack driver with both the Sierra and Berger 80 gr. bullets, but I think the Sierrs do alittle better past 400 yrds., but want to do a side by side to make sure. You won`t get the veloicity I get with the 6mm case, but that just mean you`ll have to give your scope a couple more clicks. Your 250 AI should make a good long range coyote gun.