I use 'rain gear' in temps well below freezing but I do no go from cold to hot in a hurry - I warm the rifle slowly and then it spends the night in the house. My grandfather always brought his side hammer in the house after hunting - took the rain gear off and stood the rifle up behind the wood stove. With the gear off the warm air would pass through the rifle and suck all the moisture out of the powder. Now if he felt he got the powder 'WET' hunting that was a different story - he would pull everything - but for him pulling a PRB was a piece of cake...