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Any thoughts on the best way to store firearms in very humid conditions

Pilgrims Pride

NES Member
Dec 26, 2005
America's Hometown
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I have one of those stack-on safes. It is more like a cabinet than a safe and not very well sealed.
Anyway, I had to move it to the cellar this year and it is very humid there.
I'm concerned about rust.

I have read about the golden rods and some other desiccants.
Any thoughts?
Yes to both and a dehumidifier in the basement. Preferably one that vents outside, otherwise it heats up the basement to ~80F!
Also, make sure you regularly coat all the metal parts of your stored firearms with a good rust preventing gun oil or grease.

I recommend Birchwood-Casey's Sheath, or Break Free, or Eezox. I keep an oil can and a rag near my safe to make it easy to remember to wipe down my guns as I put them away.
I have a friend who has the same situation. Worse yet is he shoots corrosive ammo in his milsurps. Normally this is no big deal if you clean up using water based cleaner and oil the bore afterwards, but even after doing so he still wound up with rust in the bores. He started using regular automotive oil to coat the insides of the bores after shooting and has finally had success.[rolleyes]
I myself would use something like Kroil along with a dehumidifier, or golden rod. A good wipe down with a quality oil like Break Free Collector, or Kroil will keep rust away. Probably a good idea to take rifles out of the stocks and wipe down underneath the barrel and receivers to prevent moisture from gathering where the wood meets the metal. If you're using a golden rod be careful about any leather slings you may have on rifles because dehumidifiers will dry out the leather and make your slings brittle, especially old military slings.
Two dehumidifers in my basement, and yes, as stated, it gets mighty warm!

I use big dessi packs, and "recharge" 'em.
I really don't think I could fit any Golden Rods in my safes![shocked]

I do not know where you are located, i would suggest an air conditioner in
your basement. Dehimidifiers create too much heat and can actually operate
in the reverse and cause more problems.

I have one of those stack-on safes. It is more like a cabinet than a safe and not very well sealed.
Anyway, I had to move it to the cellar this year and it is very humid there.
I'm concerned about rust.

I have read about the golden rods and some other desiccants.
Any thoughts?
Keep an eye on the MidwayUSA monthly sales flyers. Golden Rods go on sale every once in a while for a fraction of what you'd pay for one in a gun shop. I use them in two of my gun safes with great results.
I would urge caution in using heat-type "dehumidifiers". It seems to me that they really don't dehumidify the air - if anything the warm air can hold a good deal more moisture than cool air can.

These might keep the vapor from condensing as quickly, but I'm pretty sure that moist air will cause rust even if it's non-condensing.

Someone want to correct me here, or clarify? Seems like a crock.
joe6486, it depends on where the location is. I tried the dehemidifier route,
i had it in my basement. It got up to 80F down there. The other problem was
the water pipes were sweating, more condensate, so heat does bring in
a whole host of problems.

The best may be AC, i know someone who reloads, i trust his judgement
and he put an ac in a basement window......

Bought the golden rod


I bought the golden rod.
Now where exactly should I position it in my safe?
How do I know it's working?
I plugged it in to be sure the plug I'm using is OK and I notice that it doesnt make any noise.
Bare with me folks. The last place I stored my things was not humid at all and this was never a concern.


Most rods require that you keep them horizontal. Bottom (floor) of the safe is best. If you plug it in and give 5 miunutes it should become warm to the touch. I've had great luck with mine, but then again the surrounding environment is not overly humid.
I just wrote a reply and apparently waited too long to submit--the browser must have performed an auto refresh cause the post disappeared right before my eyes [crying] Let me try this again...

Consider getting a hygrometer to measure relative humidity (RH). I don't think I have a humidity problem in my safe but am going to install one to monitor the conditions (i'm an engineer, so these things interest me).

Any place that sells weather monitor gadgets should have them. Extech ( http://www.extech.com ) out of Waltham, MA makes a bunch. Grainger sells this Extech model ( http://www.grainger.com/Grainger/wwg/itemDetailsRender.shtml?ItemId=1613590686 - $39) that records Min. and Max. RH values so you know the RH history. Also, the indoor/outdoor probe would tell you the RH in the safe as well as in the room.

The RH should be below 50% to help resist corrosion. Below 40% would be better but if you have wood (stocks, grips, etc.) you don't want to dry the safe out too much (keep above 35%?, not sure).

Joe6486 - I don't have a scientific explaination for you but there are references for using RH as an indicator for an environment that will encourage corrosion/rust. I'll ask some uber geek people I know for a full explaination. You have a good question there.


Springfield Armory relic storage:

Corrosion explained:

Typical RH storage values:
More thoughts

I did some more thinking about this problem, and the "golden rod". I also dug around a little more, since I wanted to make sure I understood how rH worked.

There's no doubt that reducing rH reduces risk of corrosion, but I was trying to figure out how a heat source would help.

I'm pretty sure it doesn't - on its own.

Heated air can hold more water than cold air can, so if anything, heating with a golenrod or light bulb will make things worse.

However, if you heat air locally, *and then vent it*, that hot air (now carrying more humidity) is expelled, and replaced with cooler air that is presumably carrying less humidity.

So inside a well sealed safe, I doubt the heat source will do anything to help at all. What it will do is reduce the chances of condensation (since the air can hold more water), but unless your guns are going in really cold this is unlikely to be a problem.

My suggestion is to forget about the golden rod, and get a nice bucket of dessicant material. Cheap, and it'll certainly work.

Someone correct me on this if possible, but I'm pretty sure products like the golden rod are giving a false sense of security.

[ Disclaimer: yes, I'm a nerd, but not one specializing in thermodynamics. ]
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I'm no expert either, but the way I understood it, RH is only one factor, of course you want it in the dry and comfortable range, but temperature swing is also an important factor, with swings in temp comes condensation, that is the real enemy. Part of the golden rod claim is that it equalizes the temp within the safe and eliminates the chance of condensation. ........................... Just my take on it.
Okay, more research! But first let me say that this is a great forum because Bob asks a simple question and we all get to debate this in a civil manor (at least thus far!). So this is probably more than Bob, the OP, ever wanted to know but it’s something I always questioned myself: what do those goldenrods really do, if anything?

Joe, I found this article which explains how RH chemically contributes to corrosion/rust.

…the RH dependence of metal corrosion reactions is complicated by the inevitable presence of water soluble salts, which begin to absorb water from the air at a specific value of RH, above which they provide a film of watery liquid which vastly accelerates metal corrosion reactions.

From http://www.padfield.org/tim/cfys/soroe/soroe.php

I do agree with you Joe in that corrosion may still occur in warm air with a lower RH, but corrosion is at it’s worse when the RH is high. If you look at the previous links you'll see that the RH is the first environmental priority.

So to prevent corrosion:

Most importantly: Coat the surface to prevent interaction with water
Secondly: Keep the RH low, below 50%
Lastly: Avoid high temperatures

Consistancy is good too, but I'm not sure the goldenrod really helps in that area.

I bought the Extech RH monitor yesterday at U-DO-IT Electronics (I got the last one). It works okay for the price. My safe reads 67% RH, at 72 F, which is a lot higher than I thought it would be. I’ve had the safe for about 6 months and thus far have not had visible corrosion problems. However I do keep my firearms very clean and most of them still have their original finish. The glock frames show absolutely no signs of corrosion [wink]

According to the Psychrometric chart (now how geeky is that!), if get a golden rod and it raises the temperature by 5 F, then my RH will be 58%. If it raises the temperature by 10F then the RH will be 49%.

Aha! It's a matter of relative rather than absolute humidity. Even if warmer air holds more water, it's less "relative humidity" because it's further from condensation - even if it contains the same (or more) air.

So a heat source doesn't dry the air at all, but does reduce the rH. Nice loophole. Now I wonder if it's really rH or absolute humidity that really affects corrosion.

I knew I shouldn't have slept through my thermo classes.

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