Coyote season? Here they are considered vermin. Shoot on sight, day, or night. In some counties there are bounties on coyote. Centerfire 22's are most often used, due to the distances involved.
This new rimfire sounds interesting though. I'd like to see it in a semiauto, like 10-22/17, or Marlin clip fed semi. Might be a fun plinker. I may be hide bound but a 17gr bullet seems like it would bounce off or explode on anything bigger than a prarie dog.