A Gun Safe Dehumidifier is a device costing around $25 that protects a gun, more usually several guns, from corrosion.

The guns will have cost a minimum of around $500 each and probably much more. These expensive firearms are kept in a gun-safe that may easily have cost $1000. When we fire our weapons we use ammunition, which may cost anything from 75c to over $2 a round.

When we go shooting we may have to pay fees and when we get home we use cleaning materials and apply corrosion inhibitors, all of which cost yet more money.

Yes, shooting is an expensive pastime yet there are still folks who agonise about spending $25 on a dehumidifier, around the price of a box of 20 rounds.

Now before you come after me with a loaded weapon let me make something clear. If you don't have a corrosion problem with your guns you can ignore everything I've got to say. Some of you live in areas where corrosion is less of a problem and many of you have tried and trusted methods for protecting your firearms. After all, the Minutemen didn't have dehumidifiers and they got by OK.

If, on the other hand, corrosion is an issue for you, or you're not sure whether your guns are not only in the gun safe but safe in the gun safe, isn't it worth $25, or even $50, just to be on the safe side; excuse me.

A gun safe is a large sealed box. Little or no air goes in or comes out. The air inside is static, there is no air flow. When you opened your safe and deposited your gun the air in the safe mixed with the air in the room and is now

at the same temperature and relative humidity.

Let's say the temperature was 70 degrees and the relative humidity was 50%, about the RH level you would find if you were using a dehumidifier in the room. You leave the guns in the safe and go to bed. Overnight the temperature drops to 50 degrees. The safe is steel so it conducts heat quickly. The temperature in the safe is now 50 degrees.

The relative humidity in your gun safe is now 100% because cooler air can "hold" less water than warmer air. Your guns are now in air that has reached the dew point. Condensation will occur and corrosion will follow.

The solution? Remove water from the air, or warm the air, or both.

If you want to remove water from the air your best choice is to use silica gel crystals. You can buy them cheaply in bags or loose and they will absorb water. They are reusable, just heat them in the oven to drive out the moisture and

put them back in the safe.

A neater solution is to use a rechargeable dehumidifier. It contains the crystals, in a plastic case, and will operate for between one and two months before the crystals are saturated. An indicator turns pink when they are full of water. Then plug it in to your electricity supply for about ten hours and it will be ready for use once more. This type of dehumidifier will cost around $25 and should last for about ten years.

If you want to warm the air you could hang a light bulb in the safe and leave it switched on. Provided the filament doesn't burn out it will warm the air so reducing the relative humidity and prevent condensation. Not the neatest, or

safest, of solutions but it works and some folks are happy with it.

The safer and tidier solution is a heated rod dehumidifier, mounted securely to the floor of your safe. This heats up to about 140 degrees, a little too hot to hold in the hand, and warms the air. Because it is at the base of the safe it generates air circulation, by convection. The small ones cost around $25, the larger ones a little more. This too should last about ten years.

The most certain way to keep your guns from corroding is to use both. The rechargeable dehumidifier works better when there is a circulation of air and acts as a back up if the electric power fails. The heated rod should be sufficient in itself but also backs up the rechargeable unit - you may forget to recharge it if you are not using your guns for a few months.

And the cost? Two dehumidifiers, each costing around $25 and with a life of ten years, about $5 a year. That's no more than the price of a handful of rounds for one of your guns. It makes sense to me. Let me know if it makes sense to you, or am I just shooting my mouth off.