RE: 223 winchester super short mag
It should work great on coyotes. A .22 caliber bullet (.223, 22-250, etc) will kill deer, but it's not ideal. For deer, I would recommend a .243, 25-06, .270, or the new versions of these calibers in WSM and WSSM. These calibers pack plenty of punch for deer, shoot relatively flat, and still have manageable recoil.