Agreed on 1:8" twist.

For 400yrd shooting, you don't need a heavyweight bullet to do that. I shoot 50grn pills at 300 & 400 off of the bench a lot. I run 69grn pills out of 1:9" 24" and 26" barrels, even 75grn A-max's out of the 26" tube. For dropping coyotes at those ranges, no sweat even with 50grn pills.

There's nothing wrong with shooting heavy pills at coyotes, but it's not really necessary. The 75grn A-max puts a hole in one, I can say that!