I ordered an Hogue stock with full length alu bedding block for my Win 70 in .338 Win Mag. I'm aware of the possible chemical reaction/corrosion when steel is mated with alu. As a check, I took apart my SS Sendero which had been sitting in its HS stock for over 2 years and found no ill results. Any recommendations in terms of preventive maintenance ?

Corrosion between different metals requires a electrolyte to be present. If your gun were stored under salt water you probably would see a problem. This is an electro-chemical reaction, any electrical insulation will prevent it. A thin layer of oil, or wax will probably prevent any problem in a firearm stored normally.

Good luck!

not to worry, unless your talking about a spear gun..

Here is a link that describes galvanic corrosion (disimilar metals)
http://www.corrosion-doctors.org/Aircraft/galvdefi.htm

Thanks Frank, very interesting link.