I use one of the c02 dischargers. I shoot loose powder and pulling the breech plug would result in powder all over so the blast of c02 works out well for me. When you seat a load on pellets does it crush them? If so pulling the plug may still make a mess with a pellet load. What rifle do you have that is letting in that much moisture? may want to look into some ways to reduce the moisture getting into the gun rather than buying a new rifle. Do you bring the gun into a warm environment, then back out to the cold while its loaded? If so you are getting condensation in the barrel due to the temp change and you will experience that with any steel barrel.