here's a quick way of how to prevent your guns from corroding or any metal that is. You want the least amount of oxygen possible to be in contact with the guns.
So if you can put them in a sealed bag gander mountain sell's rifle bags made by the company i work for
http://www.zerustproducts.com/index.php ... oducts_allor just get some clear poly bag's even two trash bags would work put some moth balls in the bottom as it creates an ammonium gas that combines with the oxygen in the bag to create a gas that will not harm the metal on the gun. After a while it when you open it will smell like a strong ammonia smell and may make you dizzy but its completely harmless as I work with it everyday.. Its just overwelming and if you have air you'll be fine. with the bags and the moth balls zip tie the ends and viola the protection is good for 12 months and during that time change out the bag and the mothballs as any poly bag leaks over time. Our Vapor Corrossion Inhibiting bags at work are just poly-bags that are yellow with a film blown onto it for protection.
If you want samples of some VCI capsules or a product called Activpak get in contact with me as I can show you where to get upto 5 samples Activpak is a great product for corrossion inhibiting I would know I formulated it and its been working great for industrial applications.
only problem is any form of vapor corrosion inhibiting is when it comes in contact with copper it discolors it. Which does not hurt the bullets or copper at all It just essentially makes the copper more stable as copper is a very unstable metal when its in it's clean form and starts technically corroding immediately as a metal.
The discoloration is creating a film that protects the metal underneath and will not damage anything if you fire it.
any other questions feel free to ask me.