I love this kind of discussion! but it really doesn't matter when it gets reeeely cold! Here is a pic of my good buddy with a calf elk that she shot with her .308 and blue box Federal 150's when it was -35�.
When it's that cold, you must get so close it doesn't matter what you are shooting or how fast the bullets are flying. Bulky clothes and gloves make you do that, precision at long range is out of the question. If you get close enough, just be glad that you can still squeeze the trigger and hit what you aim at. She did.
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