Reloading ammo for long-term storage

Status
Not open for further replies.

BSA1

member
Joined
Apr 20, 2011
Messages
7,492
Location
West of the Big Muddy, East of the Rockies and Nor
I am a experienced reloader wth many thousands of rounds and calibers. Most of the ammo I reload are shot very quickly.

My question has to do with reloading for long-term storage (20 yrs. or so) such as in a military steel ammo can and temperature controlled environment. Does anyone that does this do anything extra to preserve the loaded round such as adding sealant around the primer and bullet?

My thought is that when sealed in ammo can the loaded rounds should be fine.
 
Last edited:
The sealed, metal ammunition cans works for the military.

Add a small desiccant pack in the can to care care of any errant moisture.
 
Correct, the metal cans are watertight and will keep out moisture. Heat is another matter-- store your ammo where the temperature is as low as possible. Optimally the storage should be in a cool dry area off the floor, but for most of us a refrigerator that large is somewhat impractical. Therefore store it inside, in an air controlled room with good air circulation year-round. A spare room is good, cooled in summer and heated in winter although that last one is not necessary.

Primer sealants and the like are unnecessary unless you plan to carry your ammo underwater as the military does from time to time. Using them might just allow some chemical to get into the primer itself, rendering it dead. I wouldn't take a chance.
 
in an ammo can with a good gasket in a climate controlled area, they should last as long as you do. a small pack of desiccant wouldn't be a bad idea.
 
I will agree on the ammo can part. You want an area that has a stable temp like a basement. There really isn't a need for climate control. A basement will swing temps at a very slow pace which is desirable if there is no conditioning in the space.


Brought to you by TapaTalk.
 
If the basement has air conditioning and heating it is climate controlled.

Yeah, I get that. But the vast majority of basements are unfinished and not conditioned. As long as you avoid rapid temperature changes you are fine.


Brought to you by TapaTalk.
 
i use ammo cans and now the plastic coffee cans. the plastic coffee cans seem to work well. i have some with ammo in them for over five/six years and it looks as good as the day it went in. but army ammo cans is the best. i got one can of reloads that was done in 1985 and it is as good as day one.
 
The lifetime of your ammunition will be primary determined by the lifetime of the gunpowder inside.

Gunpowder is a high energy compound that breaks down over time. It is mixed with stabilizers that are consumed during powder deterioration. At some point, no more stabilizers.

Nitrocellulose-base propellants are essentially unstable materials that decompose on aging with the evolution of oxides of nitrogen. The decomposition is autocatalytic and can lead to failure of the ammunition or disastrous explosions.
ROLE OF DIPHENYLAMINE AS A STABILIZER IN PROPELLANTS;
ANALYTICAL CHEMISTRY OF DIPHENYLAMINE IN PROPELLANTS

http://www.dtic.mil/dtic/tr/fulltext/u2/783499.pdf

Heat, as you can see in the report, will age gunpowder

Propellantaging.jpg

Heat is the primary enemy of gunpowder. If you search the literature you will find that suspect gunpowder is aged in 150 F ovens. If the stuff fumes in a month it is further tested for stabilizer content. The US military scraps the stuff when the stabilizer gets to less 20% original content. Heat is bad, more heat is bad, very hot is bad, bad, bad.

A rule of thumb for safe gunpowder storage is 20 years for double based and 45 years for single based. Storage in hot, like 120 F attics, will dramatically reduce the lifetime.

Humidity is bad because water is a polar molecule and it interacts with the double bonds on the nitrocellulose molecule, breaking the powder down. Water also wicks the nitroglycerine in the grain to the surface changing the burn rate of the powder. Anything ionic, like rust, is just as bad.

Primers last a very long time, current styphnate primers have a much longer storage life than gunpowder. I asked an insensitive munitions expert and he did not know. Gave a “forever” sort of estimate. Obviously it is not forever, but it might be longer than our natural lives. Which for all practical purposes, is forever, unless you believe in reincarnation and plan to will the stuff to yourself in your next incarnation.

The best storage conditions for ammunition is unchanging arctic. Totally cold and totally dry.
 
A couple of years ago, I found a box of .357s I loaded in 1980. They had been in a dresser drawer at Moms for 30 years. The brass wasn't very shiny but they shot fine.
 
A couple of years ago, I found a box of .357s I loaded in 1980. They had been in a dresser drawer at Moms for 30 years. The brass wasn't very shiny but they shot fine.

Hence my question about use of a sealant to prevent humidity creeping into the case and affecting the powder.

I have some factory ammo that has been stored for 20 years in ammo cans. I probably should test fire some of it.
 
When I load ammo to be put up, I tumble the loaded rds in clean media with car polish. IME, standard brass polish doesn't keep the brass in good condition very long.

SlamFire,
Thanks for the info.
 
The only load I make up for long term storage/emergency use is a .357 with a 158 LSWC. The bullet is Hornady swaged SWC, liquid Alox coated, so the front seals pretty good when I crimp into the waxy, knurled surface.

I use Hodgdon Universal for it's clean burning and claimed cold weather performance. It's a single base powder, didn't know they were longer lasting, bonus!

I use Markron sealant on the primer. Probably could have bought nail polish, but I have the Markron, so I'll use it up.

I like my loads to be individually sealed and not depend on a container to keep them watertight.

Maybe it's overkill, but I have great confidence in that ammo and all my magnums shoot it well.
 
Don't tell my wife but I use our foodsaver for small conveience packs of ammo for hunting. I'll do 5rd packs of 30-06 to carry for just in case ammo while tromping around up north and similar sizes for shotgun ammo while hunting around water.
 
As I have stated in the past our GOV has spent countless hours and cash to find out what the best/safest container to store ammo in is. I for one do not want to reinvent the wheel as it has already been thoroughly done. Additionally I am a bit lazy at heart to boot.:D I do put my ammo in labeled Zip-Loc freezer bags in specific quantities before putting them into the ammo cans for ease of removal/ID at a later time however. If kept in normal living environment my ammo will last longer than I will ever need it I am willing to bet.:)
 
I've carefully stored my reloads in re-used factory paper boxes sitting on a shelf in my unclimate controlled gargage since about 1968. So far it seems to be holding up well, at least in those calibers I still retain some of my first stuff.

Powder is a solid chemical compound, it doesn't care a bit about stabile or changing temps or intense cold but it does care about getting hot for long periods. Heat accelerates decomposition in any chemistry, the higher the heat and the longer the exposure the more it will break down.

There are so few open air holes into a cartridge that ambient humidity doesn't mean much either.
 
Cool dry place. Ammo can last a surprisingly long time.

I have some ammo for my 8mm Mauser that was loaded in 1935. It still shoots fine, and I doubt it was stored under optimal conditions for the last 77 years (though it wasn't in bad conditions for the past 8 or so that I've had it).
 
I recommend the ammo can and a desiccant pack. Thats what I have used and continue to use.

I was visiting with my parents a few weeks ago and was watching my mother use her FoodSaver vacuum sealer. This gave me an idea.

Went to Wal-Mart and got one of these:

http://www.foodsaver.com/product.aspx?pid=7076

Only cost me $20 + $8 for some one gallon bags. You can put about 100 rounds of .223/5.56 ammo in the one gallon size bags easily. It provides a good second barrier. If it came down to needing it, you can treat it as a light battle pack. Plus you can vacuum seal a bunch of other stuff like parts,components, food, pistols, etc.
 
I have had fantastic results using a vacuum sealer to seal up my ammo then throw it in the ammo can. I would imagine it would last forever that way.
 
The ammo can is probably your best way to go. I've shot my own reloads (~21 years) that have been stored in paper boxes and MTM ammo boxes that functioned perfectly. They were climate controled to a point (heated in the winter and cooled in the summer) but were kept at normal home humidity. They all functioned fine.

I believe the key is keeping them dry, avoid excessive humidity, and within reasonable temperature limits.
 
Status
Not open for further replies.
Back
Top