tape/balloons for the barrel, either has worked for me in the past.
wipe down your rifle with an oilcloth/towels at the end of each day.
If you're hunting in dark timber you probably won't have a shot more than 50yrds out, so a quick rifle like the cz will probably be ideal. A 150+grain bullet should be fine for cows at least. If you like your rifle and you're good with it, that's half the battle. If you spot an elk, then probably it is about to spot you, and you have about 5 seconds to do something.
Do yo have time before your hunt to bed your action to try to isolate it from any swelling in the wood?
I'm right about the metric system 3/4 of the time.