Coyotes aren't endangered.
Blast some! 
Regarding the 50 = 200, it's good enough to get pretty close on paper but truly zeroed for 200 means shooting at 200 IMHO.
For my guns, all platforms from 223 to 3006, there is a
slight L or R deviaton that isn't just the wind.
Goes without saying that changing bullet weight means starting at square one.