Run with very, very light amount of ultra thin oil in winter: if it doesn't flow ***VERY*** easily when the gun is cold in your hunting situation (ex: at -30*C sitting in the blind) then it is too thick. In my personal experience they become a problem only when the oil is too thick: it has to be able to move very freely out of the way of all machined parts, and not create a hydraulic lock or push parts out of alignment.
These modern guns are not old battle rifles that can run half full of mud, corroded ammo, axle grease and fingernails (removed by Garand thumb). I had a Tikka rifle that due to tight machining using anything other than the most viscous oil, oil runny as water at -35*C, it would hydraulic lock in the bolt and have FTF and half second delayed fires.