I posted this several years ago (December 04, 2018), and a number of folks said it was helpful. Take a look.
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Hello friends,
Here’s some thoughts on rust prevention and related issues. Many people don’t have a problem because of their physical location and circumstances… but I thought I’d put some addition comments here to consider.
Protecting guns from rust can have a number of issues to address. Depending on your situation, there are multiple concerns and protective options to consider.
The number one hazard, or at least the most common for your guns is moisture. Several of the previous posts have already touched on moisture and countermeasures, but if you’ll excuse my “return to basics” here… I’m sure somebody will gain some new perspective.
There is always some amount of moisture in the air, even in the driest areas of a desert. In practical terms, the higher the temperature of the air, the more moisture it can hold. The most common way this is measured / described is the Relative Humidity… for a given temperature, it describes what percentage of the air’s capacity to hold moisture, is actually present as moisture. Example: when you hear “its 80 degrees and 60% relative humidity”, it doesn’t mean 60% of the air IS moisture, its that the amount of water in that air is 60% of what it can hold at that 80 degree temperature. If the temperature drops, like it commonly does at night, the relative humidity will increase to a higher percentage… although the amount of actual water in the air is the same. When the temps go down even more, to the point where the air is saturated with water (can’t hold any more), you have 100% relative humidity… and probably fog-like conditions and/or dew forming on everything. This situation when water changes from a gas to a liquid is sometimes called a “condensing atmosphere”. It is the same thing when you operate your air conditioner. The refrigerant coils are so cold, that when the air is forced over them, they drop out the moisture as condensate. Moisture condensation is not what you want on your guns… whether they are in your safe, your vehicle, or in a closed gun case.
This changing relative humidity issue can be a real problem, particularly if you have your gun safe in the garage, basement, or anyplace where the temperature can drop considerably. It is possible for the internal temp to drop enough to actually condense micro-droplets of water onto your guns, beginning the rust damage. You may not even realize it, since when you eventually open the safe to look at your guns it may be warm enough at THAT time to re-evaporate the previously condensed water. There will be no evidence unless you look carefully, at the right time.
If you have your gun in a foam-lined plastic case, there may be water vapor in the foam. If the temperature drops enough inside there, you have the same potential problem.
Your BASIC goals are:
To reduce the water (humidity) in the air around your guns.
Always maintain a storage temperature high enough to avoid condensation.
Apply a protective coating on your guns to isolate the metal from moisture.
Avoid dirt / deposits on your guns that can attract moisture and hold it.
The DETAILS… You want to do the following things the best you can:
1. Keep the gun clean, with no soiling or other material that could attract and hold moisture on a gun surface. Inside and outside… everything matters. Even fingerprints can eventually do damage.
2. Reduce the moisture in the air that will touch your guns as much as practical, to assure you do not have a condensing atmosphere at any time. You can consider a dehumidifier, indicating silica gel that absorbs water (and can be regenerated / reused), etc.
3. Maintain the temperature of the gun and whatever place you have it above a point where condensation could occur. If possible avoid safe installations that will suffer large changes in temperature. In addition, you can put a specialty heat strip in your safe… designed for that purpose, or even an incandescent light bulb always on to slightly raise the internal temperature. Be sure not to lean any of your guns directly on the heat source though… you could damage them.
4. Use a coating to protect all the surfaces of the gun. Gun oil, wax, grease, silicone, etc. This makes a shield on the metal.
5. Use moisture free sleeves (rugs) to store the individual guns if possible. I use the Bore-Stores silicone cloth products, sized to the individual firearm. There are other options.
6. Do not store anything potentially corrosive or reactive anywhere near your guns.
Anyway, I hope the above helps someone. I live in South Florida so humidity is always a concern. In 40+ years I’ve never had any rust on any gun.
Best wishes everyone,
Roger aka Mr. Wonderful