I personally use gun oil on my stocks, as I find it's high viscosity helps soak into the wood if it shrinks or expands, should it come into the cold for a long time. Another simple solution is to do as the Russians did, and bathe your rifle in cosmoline

. A more modest, simple method, is make a little tight crate or drum, and fill it with a mix of motor oil, auto transmission fluid, and anything else. Worst come to worst, you can use a drum of crude oil and add gelatin powder. These are things I've heard in the outback and boonies. A friend's great grandpa brought his Garand home, cleaned the bore out, and dunked it whole into a drum of motor oil. Left it there until just recently, when it was found after buddy poured out the drum. Who knows? Just my two cents.