I have a switch barrel rifle with .30-06, .243, 6.5x55 and .300WSM.
My son has the same rifle in .300wsm
You've had lots of good advice here. I echo that "goats" are pretty easy to kill, so any your rifles are fine. I would take whichever rifle and load you can shoot the best with. If there is a tie in that contest, take the rifle/load with the better BC, to make dealing with the wind, which unless you're very lucky, WILL be a bear in Wyoming.
Good luck - I leave for Montana for pronghorn on Wednesday myself. It's windy there too.
Rex
