i would have said exposed for open country as the liklihood of bumping zero is low, and you can confirm you are set on zero periodically or prior to taking a shot if needed. However, if your turrets are not sealed then yes, i would keep them capped. Have a think though so you can know what features you are looking for if/when you upgrade.
I have scopes with exposed turrets on my LR rifles, open country or not there is still obviously the potential to get rubbed on your pack etc if slung and the turrets turned, you just need to always be in the habbit of always quickly casting your eye over them to make sure they are on zero, its no biggie.
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