I'd grab my Browning A-Bolt in 7mm-08.It would get a thorough cleaning removing all oil then lubed with a teflon-based lubricant.Freezing rain would mean I'd be wearing waterproof clothes so the rifle would be under my jacket while on stand(just to be on the safe side-we're talking a million bucks here).Ammo would be what works best in my gun-140gr Cor-lokts.