They are using a 7mm STW. I have heard from a few fellows they like this round for Coyotes.
So if a 7mm STW can be used why not a .300 Mag.
Google is a handy thing.
I never said it wasn't a better cartridge for long range but most people don't shoot that far or even close when calling dogs so meant it was impractical. More expensive to shoot and more than you really need. If your shooting 400 + all the time ya go bigger but in most cases your not shooting past 300 when calling I used to run a 25-06 as my dedicated coyote gun but went to the 22-250 because it was all I really needed and cheaper to shoot
If and when my BLR 22-250 wears out or my kids steal it .. I will replace it with another 22-250 in a T3 Tikka like my 300WM and top it with a mildot scope , probably a 7x21 or there abouts ..