You never said what kind of rifle you are using.
I finished my last hunt at -32 deg C, and I didn't do anything to my rifle. However, I also don't drench the firing pin in oil, nor the trigger. The bolt gets a wipe of oil, but it is not a visible layer.
It seems to me that most of the stories about freezing problems in cold weather come from over-liberal use of oil squirted into any holes that present themselves on the rifle, without going in and cleaning up.