Ideal humidity for ammo storage

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  • Goodcat

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    It's been discussed a billion times online, but curious about ingo opinions. I have a... ammo closet, we'll call it. Insulated to the outside wall and ceiling but also sealed from the house other than a couple walls backing up to climate controlled areas, on a slab. I'm considering installing ventilation and while challenging, think a hole in the wall with a register booster installed may help. That's being said, what humidity would you feel comfortable storing ammo at? I'm not interested in hearing about ammo cans, desiccant, etc because most is treated as such. The hypothetical question is, if you had loose ammo and gunpowder, what humidity level would you consider OK for long term storage?
     

    BehindBlueI's

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    The military manuals on the storage of ammunition does not have a single mention of "humidity" other than for electronics equipped munitions (ie guided missiles). That's probably a clue it doesn't matter. Other than "out of the elements" and "sufficiently ventilated" there is no concerns about climate.

    Ammunition is not as fragile as many seem to think. Feel free to take whatever precautions you like, but it's just to make you feel better and perhaps to keep some cosmetic blemishes at a minimum. It won't affect the viability of the ammunition.
     

    Goodcat

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    The military manuals on the storage of ammunition does not have a single mention of "humidity" other than for electronics equipped munitions (ie guided missiles). That's probably a clue it doesn't matter. Other than "out of the elements" and "sufficiently ventilated" there is no concerns about climate.

    Ammunition is not as fragile as many seem to think. Feel free to take whatever precautions you like, but it's just to make you feel better and perhaps to keep some cosmetic blemishes at a minimum. It won't affect the viability of the ammunition.

    Thats good to hear, thanks. I've always wondered why even poorly stored ammo has never failed to go bang after 10 years.
     

    BE Mike

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    Yep, I'd say as long as the ammo is not exposed to extremes in temperature, especially heat and not exposed to extremes of humidity, it will probably last a long, long time. That being said, you said you have ammo stored loose. I'd be careful not to have different metals touching or store it in a container that would absorb and retain moisture. I have a dehumidifier in my basement. Humidity is kept around 50%.
     

    BehindBlueI's

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    As a followup, in the name of science (and not forgetfulness) SOMEONE in my house ran a speed strip of PDX-1 .38+P through the washing machine in the pants pocket of my pants after mowing the lawn.

    I'm not sure the humidity in a washing machine, but the cartridges fired just fine at the range. I'd probably not recommend storing ammo in a running washing machine...but they were nice and shiny afterward.
     

    BE Mike

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    My father had some .45 ACP match ammo in the top drawer of a filing cabinet in the basement. The basement was flooded, but the water level never came near the ammo. He shot some of the ammo a few years later and it barely got out of the end of the barrel. As he never did remove the ammo, I expect that the high humidity over a long period of time finally got into the powder.
     

    snapping turtle

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    The only ammo issue I had was on a three day squirrel hunt which we were using canoes. Had a 35 mm film container with some Winchester wildcat rounds in it. Somehow it got some water in the canister and the lid was shut. must have soaked them good. They had nice dents on the edge but no bang. Had to borrow 7 from hunting partner. Same with some old paper shells in shotgun. Had stains or water marks outside and only about half went off. Then again I am fifty two and that ammo was older than I am.
     

    Mgderf

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    I'm 58 and I've shot a lot of Mil-surp ammo that was older than I am.
    Some mis-fires here and there, but for the most part, (90% or so) went bang as expected.

    No clue how any of it was stored, but I know for a fact it had to have been stored in different manners/fashions/humidity.
    I'm talking around 10 different calibers over 30 years or more.

    If it was manufactured properly, it should be viable for decades, even under some fairly harsh conditions.
     

    BE Mike

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    I'm 58 and I've shot a lot of Mil-surp ammo that was older than I am.
    Some mis-fires here and there, but for the most part, (90% or so) went bang as expected.

    No clue how any of it was stored, but I know for a fact it had to have been stored in different manners/fashions/humidity.
    I'm talking around 10 different calibers over 30 years or more.

    If it was manufactured properly, it should be viable for decades, even under some fairly harsh conditions.
    That military ammo had crimped and sealed primers, as well as, sealant between the bullet and case. Civilian ammo generally isn't quite that well insulated.
     
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