Storing ammo in basement

[357smallbore]

I just moved into a new home. It has a finished basement that is temperature controlled. All my ammunition is stored in 50 cal ammo cans with good seals. Is it best to store these up off the ground on a pallet or two? I have a dehumidifier as well and have desiccant packs in the ammo cans.

 

[Slamfire]

I just moved into a new home. It has a finished basement that is temperature controlled. All my ammunition is stored in 50 cal ammo cans with good seals. Is it best to store these up off the ground on a pallet or two? I have a dehumidifier as well and have desiccant packs in the ammo cans.

I think this more of an ammo can storage question than ammunition.

Cool and dry is the best storage conditions for gunpowder, and then hence, ammunition. Extremely dry might not be the best for match 22lr has that stuff is coated in grease, and I have noticed, the boxes for Eley match are actually sealed in such a way to prevent drying of the grease coating. But, for a general statement, because gunpowder deteriorated exponentially with respect to temperature



cool is much better than hot.

Something else, inspect your ammunition. Even with cool, and dessiccant, the gunpowder inside the case is still deteriorating. So look for signs of NOx outgassing from the gun powder.

On this round, corrosion around the primer was a give away, that the powder had deteriorated internally.



One of the NOx molecules created by the deterioration of gun powder is nitrogen dioxide. That stuff is horribly reactive, and when a NO2 molecule bumps into water (call it humidity), it changes into nitric acid gas. Which is horribly corrosive. These compounds will eat pin holes in brass, as can be seen in these photos





You see green tarnish on the outside of loaded ammunition, it could be from NOx releases when gunpowder breaks down.



In terms of storing ammunition cans, if the floor is wet, the bottom of the ammunition can will rust. Ammunition cans are made from cheap steel, painted for corrosion protection, but I have had them rust on the bottom in the garage. So, if you are worried about your ammunition cans rusting on the bottom, I think elevating them off a basement floor is a good idea. Won't do anything to slow the deterioration of the gunpowder in the cases, but it will keep the bottoms of your cans from rusting out.!

 

[LaneP]

If there's a barrier between the cans and any bare cement, you'll be fine. I've stored ammo in similar conditions since 1991 (the year I bought the house I'm in now).

 

[ColtPythonElite]

I have been storing ammo, powder, and primers in my basement 30 years with no problems. The majority of ammo it is in the factory cardboard boxes. I run a dehumidifier. Never had a problem. The ammo that I do have in ammo cans is sitting directly on the concrete.

 

[lightman]

I just moved into a new home. It has a finished basement that is temperature controlled. All my ammunition is stored in 50 cal ammo cans with good seals. Is it best to store these up off the ground on a pallet or two? I have a dehumidifier as well and have desiccant packs in the ammo cans.

If your basement is unlikely to flood your ammo should be fine. I would keep your ammo cans up off of the floor. I built shelves for mine from concrete blocks and 2X8's. A pallet would work but takes up more space than what I built.

 

[Chevelle SS]

I store 99% of my ammo in 30 and 50 cans in my basement and haven't had any problems. They are on the floor but on a piece of carpet.

 

[Walkalong]

Absolutely have it up off the floor, things happen, although I hope you never experience it, cheap insurance.

 

[American_Fusilier]

I store mine in the basement too. In ammo cans with a desiccant packs I the ammo cans, and primer containers, everything is off the floor and we have a dehumidifier running as well. I've never noticed anything to be concerned over

 

[High Plains]

Since 1998 I have shotgun and rifle ammo in my basement. Sealable plastic containers, surplus military ammo boxes and plastic containers made by MTM hold it all. There have been no signs of brass deterioration. As long as the temperature remains stable and no moisture is in direct contact with the ammo all things ought to be OK. The basement stays cool in the summer, plus the arid SW Kansas climate is a bonus. Primers stored in their manufactures cardboard boxes are in the same room and have been fault-free.

 

[Demi-human]

Absolutely have it up off the floor,

Indeed. Especially if the concrete is not sealed. Concrete is porous and will weep moisture from under it, drawing with it the salts and effluences from the unhydrolized cement. The cool spot under the can will draw condensation from the air as well, even in climate control.

A painted floor and shelving is best for protecting ammunition cans in Michigan.

If a creek runs through your basement every spring, like mine, well, how’s your attic?

 

[Gone Hiking]

Most of my ammo and reloading stuff is on heavy duty wire shelving racks in my unfinished, but HVAC controlled and relatively dry basement (as in I never get water on the floor or sweating on pipes). I say "relatively dry" as basements are inherently more damp than above grade living space. Since moisture is highest close to the floor, I keep brass and bullets on the bottom shelves as those are least affected by moisture. I keep primers, powder, and loaded ammo on the shelves above waist height. All primers are in USGI ammo cans with desiccant. Loaded ammo is in everything from factory cardboard, to USGI ammo cans with desiccant, to 50-100 round plastic ammo boxes. I've never found ammo degradation of any sort.

 

[Steel Horse Rider]

Custer has pretty low humidity so if the basement is cooled I don't think you need to worry.

 

[plainsdrifter]

I store 99% of my ammo in 30 and 50 cans in my basement and haven't had any problems. They are on the floor but on a piece of carpet.

Carpet can harbor a lot of moisture. In fact I've seen metal rusted out on the bottoms that sat on carpet even on ground level concrete that has moisture emission issues.
Ask a flooring guy.
Airflow all around cans is best. Or on elevated shelves.

 

[Bruce D Pease]

Ammo cans on industrial strength wire racks at least a foot off floor. Have had no problems

 

[Artg56]

For 50 years I stored ammo both in cans and original cardboard boxes in basement with humidifier running, all in a steel cabinet elevated 3” off the floor. Over the last year I used thousands of rounds stored since the seventies and eighties in various calibers and except for (2) .22 rounds it all functioned. Primer’s and power on shelves above my reloading bench in original packaging.

 

[Hangingrock]

A dehumidifier in the basement solves a lot of problems!!!!!!!!

 

[Palladan44]

I keep mine off the ground with a pallet so air flows underneath.
Temps fluctuate here from a bone dry 30 below zero to 90 and high humidity.
You're doing everything right. If you want to go one more step.....
You can make your own dessicant packs using the hypo allergenic kitty litter which is made out of silica gel. Not the blue/Grey clay smelly crap. This stuff is whitish clear and odorless. Bout 15$ from Wally world.
Use coffee filters w/ staple or I put 2 or 3 tablespoons in a baby sock, then zip tie shut.
Cheap insurance.

 

[Reloadron]

I just moved into a new home. It has a finished basement that is temperature controlled. All my ammunition is stored in 50 cal ammo cans with good seals. Is it best to store these up off the ground on a pallet or two? I have a dehumidifier as well and have desiccant packs in the ammo cans.

They will do just fine. Elevating them off the deck a few inches certainly won't hurt.

Ron

 

[Mr. Pepper Nose]

I really like the plastic MTM crates with the seal. At one point I was also removing ammunition from the cardboard boxes and using the Mini MTM sub-containers, but it became burdensome and also made checking batches for recalls a PITA. I figure anything with a seal stored in a climate controlled environment is solid. I also keep everything upstairs; heat rises and all things held constant, relative humidity reduces with temperature increases.

 

[roval]

I think this more of an ammo can storage question than ammunition.

Cool and dry is the best storage conditions for gunpowder, and then hence, ammunition. Extremely dry might not be the best for match 22lr has that stuff is coated in grease, and I have noticed, the boxes for Eley match are actually sealed in such a way to prevent drying of the grease coating. But, for a general statement, because gunpowder deteriorated exponentially with respect to temperature

View attachment 1082455

cool is much better than hot.

Something else, inspect your ammunition. Even with cool, and dessiccant, the gunpowder inside the case is still deteriorating. So look for signs of NOx outgassing from the gun powder.

On this round, corrosion around the primer was a give away, that the powder had deteriorated internally.

View attachment 1082456

One of the NOx molecules created by the deterioration of gun powder is nitrogen dioxide. That stuff is horribly reactive, and when a NO2 molecule bumps into water (call it humidity), it changes into nitric acid gas. Which is horribly corrosive. These compounds will eat pin holes in brass, as can be seen in these photos

View attachment 1082457

View attachment 1082458

You see green tarnish on the outside of loaded ammunition, it could be from NOx releases when gunpowder breaks down.

View attachment 1082459

In terms of storing ammunition cans, if the floor is wet, the bottom of the ammunition can will rust. Ammunition cans are made from cheap steel, painted for corrosion protection, but I have had them rust on the bottom in the garage. So, if you are worried about your ammunition cans rusting on the bottom, I think elevating them off a basement floor is a good idea. Won't do anything to slow the deterioration of the gunpowder in the cases, but it will keep the bottoms of your cans from rusting out.!

what are the variables in the columns from the table ?

 

[Slamfire]

what are the variables in the columns from the table ?

Temperature and the lifetime of the propellant. Table is on page 5 of IATG 07.20 International Ammunition Technical Guideline: Surveillance and in service proof.


TM 9 1300 214 U S Military Explosives https://bulletpicker.com/pdf/TM 9-1300-214, Military Explosives (1967).pdf

TM 9-1300-214 has this section on nitrocellulose

Section 7-7 Nitrocellulose

q. Nitrocellulose, even when highly purified, is much less stable than most of the non initiating military high explosives , as judged by elevated temperature tests. It appears to under go very slow decomposition even at ordinary temperatures, the rate of decomposition increasing 3.71 times with each increase in temperature of 10°C. The presence of moisture increases the rate of decomposition considerably and the presence also of free acid or alkali has an even more pronounced effect.

 

[HOWARD J]

Been storing ammo on shelves in basement for 4 different houses
off & on for 70 years--some ammo fired after 40 years-----works good.

 

[herrwalther]

A barrier between a concrete floor and metal ammo cans isn't required. But it is a good idea. Pallets or a similar riser can keep air flow circulating around an ammo stock better and keeps moisture on the underside of the cans low. And in a new house, you don't know if there are any wet spots in the basement floor yet that develop over the course of the year with seasonal changes.

Another wise investment is a thermometer/hygrometer readout that records the range of both. You can check the humidity at any time but not know what the ammo is being exposed to while being stored. A monitor that stores the highs and lows will give you a better idea on how to keep ammo stable for a long time. Works inside gun safes as well.

 

[Mr. Pepper Nose]

Been storing ammo on shelves in basement for 4 different houses
off & on for 70 years--some ammo fired after 40 years-----works good.

I don't doubt it, but depending on personal climate; results could vary wildly. Some states have a much higher humidity and water table. Knock on wood, my basement seems to stay dry - despite this I store upstairs.

 

[hso]

Is it best to store these up off the ground on a pallet or two?

Whether on dirt or concrete you don't want to leave them sitting on either for extended periods of time. I always set them off the concrete whether it is on a pallet or just on a pair of 2x4s to keep them off the floor.