I use my .22 Mag Spostster with a Survivor stock setup for Maine coyotes out to about 100 yards with great results. I also have a very accurate .223 Handi for long shots. Either one works great. A couple of my coyote buddies from Maine use .22 Mag Sportsters after they saw how well mine performed. One of them has a Marlin 336 in .35 Remington, his deer gun,whicj he load with 150 grain pointed bullets for coyotes, a factory round, for long range coyote hunting. He loads one in the chamber and one in the magazine tube and it works very well, knocks them down FAST....<><....
You're right about a 35 putting them down fast Andy!!
I shot one in the neck at about 40 yards with my 35 Whelen with a 250 grain Core Lokt.
It wasn't pretty!!
Alien...
Don't overlook the 22 Hornet.
A hollow point from the Hornet will make a dog real dead in a hurry.
Of course... being Marines, we have a soft spot for the 223.
A 223 Ultra with some good glass would reach out and touch 'em at longer ranges than the Hornet.
Whatever you choose... get the best glass you can afford for it.
Spanky