Sealing primers for storage ammo

[AlHunt]

OK, we've got a thread going on vacuum sealing ammo. I've got a related question but don't want to divert that discussion. I'm not sold on the need or efficacy of vacuum sealed ammo in most cases. I don't think it hurts, just not convinced it's worth the effort.

So ... what about sealing the primers on ammo intended for storage? I've been building ammo to lay up and I've been thinking about some varnish on the primers like we see on military ammo.

If the neck is sealed, it seems like sealing the primer should protect the powder and primer for years.

I'll appreciate any insights.

[Rich/WIS]

After loading I store ammo in GI ammo cans. As long as the seal is good and storage conditions are good the ammo will probably outlast you.

[Winger Ed.]

I put loaded ammo in zip-lock bags or ammo cans so they don't tarnish and look ugly nearly so soon.

As far as needing to-
I inherited some .38s and .22LRs back in the 90's that had been rolling around in my grandparents dresser drawer since the 1930s.
They lived in Mississippi, in a un-airconditioned house.
I never did any scientific accuracy tests with it, but it all worked fine.

As did the pint Whiskey bottle of holy black I inherited from my other grand parents in the Texas Hill Country.
It had been sitting on a shelf from back when muzzle loading shotguns were the rage
since they couldn't hardly afford the newer store bought shells and a gun to fire them in.
I made some home grown fireworks with it.

[higgins]

I believe the primer seal on military and factory ammo is lacquer instead of varnish. If so, maybe they use lacquer because it's thin so it will be pulled into the crack at the primer and dry quickly. There used to be sealing lacquer for ammo on the market, and there probably still is. The same lacquer could be used at the joint between the bullet and the case mouth. I've fired foreign military ammo that had clear lacquer on that joint.

[tankgunner59]

I was a part of a thread on another site years ago and a few of those guys sealed their primers with finger nail polish, or super glue.

[rancher1913]

I use ammo cans, if it works for the military, it should work for me.

[Mk42gunner]

GI steel ammo cans work fine; with the added bonus that if there is a fire, they will contain any shrapnel from small arms ammo cooking off. At least they are supposed to, I've never tested it myself.

Robert

[megasupermagnum]

I used to seal all my hunting shotgun shells, as my main target was ducks and geese. All manufacturers seal their shells crimp for waterfowl hunting ammo, but few if any do for target ammo, or general purpose field loads. I'm not sure that any manufacturer seals shotgun primers, even the military rounds do not appear to have any sealer. Over time I began to question why I went through the effort, as I had never had a single round fail to fire. So I started testing without sealer. I quickly dunked un-sealed shells in water, and found perfect performance as always. I've always cut open factory ammo, and a surprising thing to note is that even on "sealed" ammo, there are a significant number that are not truly sealed at all. There are a lot of tiny gaps on a shotgun shell crimp, and sealing them is very difficult. I've not sealed a shotgun shell since, and still have yet to have a fail to fire on a shell. Once in a while I'll have one roll around the bottom of the leaky duck boat, but they too always fire. This year I had one that was completely under water all morning, as I had dropped it before light, and did not pick it up until I got back around noon. It too fired. A shotgun shell, with no extra sealing of the crimp or primer that had been on the bottom of a boat with standing water in it for 5-6 hours had fired as usual.

Now, I don't intentionally put my ammo under water. I actually go through trouble to prevent it. If I were a military, who may need to operate in the water, I would seal my ammo again. I doubt that sealing each cartridge has any bearing on the shelf life of the ammo. A standard cartridge loaded with no sealers, stored in half decent conditions has an indefinite shelf life, at least 100 years. Nobody knows exactly how long yet, as smokeless cartridge loaded ammo has not been around long enough to break down yet. My "spare" ammo gets stored loose in a plastic bag, a small desiccant pack inside, then stuffed into an ammo can. I use both the plastic and metal cans, and find little difference in actual use. Those plastic cans are tougher than you would think, and their only drawback is they wont handle a large fall. You could get more ammo in an ammo can if you stacked each cartridge carefully, but nobody has time for that. Loosely filled, I still get about 1.5x as many in as if they were in an MTM ammo box.

[Dave W.]

On several occasions, some of my reloaded ammo was left in a pants pocket and went through the washing machine. They all still fired. You can seal the primers if you want, but in my opinion, based on "testing" I have done, it would be a waste of time.

[AlHunt]

I used to seal all my hunting shotgun shells, as my main target was ducks and geese. All manufacturers seal their shells crimp for waterfowl hunting ammo, but few if any do for target ammo, or general purpose field loads. I'm not sure that any manufacturer seals shotgun primers, even the military rounds do not appear to have any sealer. Over time I began to question why I went through the effort, as I had never had a single round fail to fire. So I started testing without sealer. I quickly dunked un-sealed shells in water, and found perfect performance as always. I've always cut open factory ammo, and a surprising thing to note is that even on "sealed" ammo, there are a significant number that are not truly sealed at all. There are a lot of tiny gaps on a shotgun shell crimp, and sealing them is very difficult. I've not sealed a shotgun shell since, and still have yet to have a fail to fire on a shell. Once in a while I'll have one roll around the bottom of the leaky duck boat, but they too always fire. This year I had one that was completely under water all morning, as I had dropped it before light, and did not pick it up until I got back around noon. It too fired. A shotgun shell, with no extra sealing of the crimp or primer that had been on the bottom of a boat with standing water in it for 5-6 hours had fired as usual.

Now, I don't intentionally put my ammo under water. I actually go through trouble to prevent it. If I were a military, who may need to operate in the water, I would seal my ammo again. I doubt that sealing each cartridge has any bearing on the shelf life of the ammo. A standard cartridge loaded with no sealers, stored in half decent conditions has an indefinite shelf life, at least 100 years. Nobody knows exactly how long yet, as smokeless cartridge loaded ammo has not been around long enough to break down yet. My "spare" ammo gets stored loose in a plastic bag, a small desiccant pack inside, then stuffed into an ammo can. I use both the plastic and metal cans, and find little difference in actual use. Those plastic cans are tougher than you would think, and their only drawback is they wont handle a large fall. You could get more ammo in an ammo can if you stacked each cartridge carefully, but nobody has time for that. Loosely filled, I still get about 1.5x as many in as if they were in an MTM ammo box.

I think that pretty well answers the question. Avoid storing ammo underwater and it should be fine.

I'm currently using recycled peanut butter jars and grabbing ammo cans when I see a good deal.

I've typically loaded a few hundred rounds at a time, as needed. The last couple of years I've been working on 500 and thousand round batches to store so my concerns have changed a little.

I appreciate all the responses.

[AlHunt]

GI steel ammo cans work fine; with the added bonus that if there is a fire, they will contain any shrapnel from small arms ammo cooking off. At least they are supposed to, I've never tested it myself.

Yeah, I'd leave that testing to professionals, too.

[AlHunt]

I believe the primer seal on military and factory ammo is lacquer instead of varnish.

That's probably it. Varnish didn't seem quite right.

[AlHunt]

On several occasions, some of my reloaded ammo was left in a pants pocket and went through the washing machine. They all still fired. You can seal the primers if you want, but in my opinion, based on "testing" I have done, it would be a waste of time.

Yeah, come to think of it, I've conducted that test a few times myself.

[jdfoxinc]

I had 3 ammo cans partially full on the floor of my store. The burglars torched the store after stealing the modern firearms. All 3 ammo cans detonated scattering flowered brass 25 yards into the parking lot. I never did find the lids.

[megasupermagnum]

I had 3 ammo cans partially full on the floor of my store. The burglars torched the store after stealing the modern firearms. All 3 ammo cans detonated scattering flowered brass 25 yards into the parking lot. I never did find the lids.

Were these plastic or metal cans? In such a fire, small bits of flying brass is the least of my concerns, but it might be good to know.

[Boogieman]

Wife left 3 38 shot loads in her pocket, unsealed hand loads, put them trough the washing machine. they all shot just fine

[Wayne Smith]

And I have twice left 44-40 BP loads in my pants pocket that went through the washer and dryer. both fired with out problem. BP and lead boolit and the washing machine - I don't think I need to seal anything more than that.

[gbrown]

Back in the 50s and 60s, pre A/C days, a lot of the older folks did use fingernail polish to seal primers. Its lacquer in an acetone or similar substance.

[Markopolo]

i have had issues with shotshells several times with failure to fire due to moisture. its not the primer that is the problem, it was the powder.. where I go duck hunting it is a tidal flat and there is a higher chance your gunna misjudge and get dunked. i started attempting to seal my shotshells with various things, but stopped putting rounds in the chest pocket and ammo bandolier on the front of my chest waders completely.. i tried super glue, lacquer, elmers, you name it. but that is my world, never had an an issue with any other ammo except shotshells. diddnt matter if they were mine or factory. now I use a zippered water resistant case for my shotshells. they still get damp and are a bit harder to get to, but they all fire now instead of Bloop...

[Winger Ed.]

I believe the primer seal on military and factory ammo is lacquer instead of varnish.

It is.
From a production stand point-- lacquer works well, and it dries much faster than varnish.
Finger nail polish is a lacquer paint product that can be substituted for sealing primers at home.

I've bought several lots of GI bullet pulls in 5.56, .30, and .50BMG.
Also GI pull down cases in 7.62, .50BMG, and .30-06.
They had a residual amounts of tar that had been used to seal the necks.

[gwpercle]

Military Ammo has/had (at least WWII 30-06 did ) the bullet sealed into the case mouth with black colored "Asphaltum Varnish " which is still available today ... the inside of the case neck and the area that the bullet touched inside the neck had a coat and were firmly held / cemented in place .
Primers were sealed with lacquer , applied after the primer was seated around the edge between pocket and primer . Lacquer dries fast and being thin (brushing lacquer) would seal any /all openings around the primer .
These two operations theoretically rendered the ammo "water proof" !
Gary
If you want to pull bullets ... seat them 1/16th inch deeper to break the seal ... makes bullet pulling so much easier !

[ronz]

https://www.brownells.com/reloading/case-preparation/primer-sealer/one-shot-primer-sealer-prod54410.aspx

Don't see the need for it
I had a 45 mixed in with range brass soaking and stirred around in soapy water for 3 days and then through the ultrasonic cleaner and still shot fine

[BrutalAB]

Seems i read somewhere that the sealing the military wanted, was more due to the abuse the rounds would endure during full auto fire. Dont remember the source, and may be an old wives tale.

[fatnhappy]

After loading I store ammo in GI ammo cans. As long as the seal is good and storage conditions are good the ammo will probably outlast you.

I do the same + toss in a desi bag.

[David2011]

I was a part of a thread on another site years ago and a few of those guys sealed their primers with finger nail polish, or super glue.

“Super glue” or any cyanoacrylate is not water resistant or proof. After a relatively brief soak (hours; not weeks), it loses its bond.