In these tests, the rifle was never brought into the warm part of the house. I did that on the last test with terrible results. Misfires, and poor accuracy. I brought the rifle into the wood room which is hardly warmer then outside at times....

If you do store the rifle, store them muzzle end down on a piece of cotton cloth or paper towel. Then if any moisture does form, it will move away from the powder charge out the barrel.