I would also suggest the one you shoot the best, and know the most about. Trajectory could be an issue with the .06 after a couple hundred yards, but if you are familiar with how it shoots then go for it.
Last week I killed this Roosevelt with my .270 shooting 130 grn Power Points. I had the option of a STW in 7mm and a 300 Win Short Mag, but I have used the .270 for more then a dozen years and I know it inside and out.
One of the things I struggle with when afield is keeping my rifle clean and in good working order. Small amounts of dust and dirt collect moisture; moisture can freeze rendering your action immovable when you need it most. I have seen this happen on multiple occasions, and over time, I’ve learned the cause and how to prevent this from happening.
The first thing that you need to avoid before going afield is leaving excess oil on the gun. Oil will trap dirt and sand in all the wrong places....