RE: Weather-proofing a rifle????
I have a ceramic coated muzzleloader, also known as TC Weathershield I believe. It has been great so far, but I have only had it one year.
For a gun you don't want to put a lot of money into, I have also used the Rustoleum Dark Gray wet sandable automotive primer that comes in a spray can from Walmart. When applied, it dries to a very durable matte gray/black, you can leave it like that, but if it rubs against anything it will leave a noticable bright spot. If you lightly rub it down with 0000 steel wool, it looks like a very deep gun blue that won't show the rub spots. I did this on a Remington 725 that had some light pitting on the barrel and it turned out beautiful, you can't even see where the damage was. The best part is it was only $5 and a little of my time. Make sure you completely degrease it first and it will last a long time, but can easily be touched up with another coat if it is scratched.