It is essential to successful hunting in very cold weather, that you clean the inside of the bolt and firing pin to remove any residual grease, BEFORE going into the field. Otherwise you could find yourself sitting across a canyon from a 180 class buck who is quietly walking away from you when you lay the cross hairs of the scope between his shoulder blades and squeeze the trigger and hear a deafening "CLICK" instead of the expected "BANG"!
Nuff said..
Nuff said..