Sealed case-mouths...necessary...or dogma?

[Moonshot]

OK, in a perfect world sealed is better than not sealed. None of my Black Hills .223 (68gr and 75gr)*, my Spier SBGD .38, or my HST 9mm (124gr and 147gr) have sealed case mouths, while only the Gold Dots seem to have sealed primers (blue ring around primer pocket).

Is there any reason to use an after market sealer (or nail polish, as I've heard this will also work) and apply sealer myself? Any reason not to? Can it cause more harm that it prevents? Can it even be done to the case mouth "after the fact"?

I understand that it is not necessary for ammo stored under "normal" conditions, but for long-term storage? This ammo does not get cycled through training - I have training rounds for that.

* Some of my earlier BH .223 (in the all red box) had red primer sealer, while newer BH (in the new red and black box) does not. I called BH and asked them about this and was told that all their ammo was sealed at the primer, but the new sealent was clear. I took this to be BS as other BH bullet weights in .223 were still being released with the "old" red primer sealer, but the 75gr OTMs had nothing.

[Unobtanium]

OK, in a perfect world sealed is better than not sealed. None of my Black Hills .223 (68gr and 75gr)*, my Spier SBGD .38, or my HST 9mm (124gr and 147gr) have sealed case mouths, while only the Gold Dots seem to have sealed primers (blue ring around primer pocket).

Is there any reason to use an after market sealer (or nail polish, as I've heard this will also work) and apply sealer myself? Any reason not to? Can it cause more harm that it prevents? Can it even be done to the case mouth "after the fact"?

I understand that it is not necessary for ammo stored under "normal" conditions, but for long-term storage? This ammo does not get cycled through training - I have training rounds for that.

* Some of my earlier BH .223 (in the all red box) had red primer sealer, while newer BH (in the new red and black box) does not. I called BH and asked them about this and was told that all their ammo was sealed at the primer, but the new sealent was clear. I took this to be BS as other BH bullet weights in .223 were still being released with the "old" red primer sealer, but the 75gr OTMs had nothing.

BH used winchester pre-sealed cases. I don't know what they use, now. I suspect it varies.

[Rich]

OK, in a perfect world sealed is better than not sealed. None of my Black Hills .223 (68gr and 75gr)*, my Spier SBGD .38, or my HST 9mm (124gr and 147gr) have sealed case mouths, while only the Gold Dots seem to have sealed primers (blue ring around primer pocket).

Is there any reason to use an after market sealer (or nail polish, as I've heard this will also work) and apply sealer myself? Any reason not to? Can it cause more harm that it prevents? Can it even be done to the case mouth "after the fact"?

I understand that it is not necessary for ammo stored under "normal" conditions, but for long-term storage? This ammo does not get cycled through training - I have training rounds for that.

* Some of my earlier BH .223 (in the all red box) had red primer sealer, while newer BH (in the new red and black box) does not. I called BH and asked them about this and was told that all their ammo was sealed at the primer, but the new sealent was clear. I took this to be BS as other BH bullet weights in .223 were still being released with the "old" red primer sealer, but the 75gr OTMs had nothing.

One can buy primer sealer. I gave away a bottle of George & Roy blue. Don't know about the Black Lucas ( the black looking tar that's seals the bullet /CM bullet.

Yes one can use nail polish

[Jeep]

Is this something that matters to a civilian or LE, or is it something similar to "could get soaked in jet fuel for 48 hours and survive..."?

LTC John George in his book "Shots Fired in Anger," reported on the difference between US and Japanese ammo on Guadalcanal. Basically, all the US ammo fired. A lot of the Japanese ammo didn't because it wasn't sealed, wasn't packed in metal cans with a rubber seal, etc.

You can soak unsealed ammo in water for a long time and most of it will still work. Some won't, though, and that is the critical thing. By contrast, you can go wading in a river with GI ammo and it will still work essentially all the time, and a belt of .50 cal. covered in snow for days will work as well.

I don't know about GI ammo and salt water; Sean or the Marines here can speak to that, but my guess is that it works fine if it hasn't been submerged long enough for the salt to corrode the metal seriously.

It strikes me that none of this will usually matter to a civilian or LE, but sealing also isn't going to hurt.

[Moonshot]

It strikes me that none of this will usually matter to a civilian or LE, but sealing also isn't going to hurt.

Buying it sealed isn't going to hurt, but what about a "do it yourself" approach? Could the primer be killed? Could sealant harm the powder or burn characteristics if it seeps in past the case head? The .mil uses one product for the primer and another for the case head. Will primer sealer or nail polish work on both?

I've got some top end (and somewhat expensive) self-defense ammo. I don't want to risk destroying it in an effort to make it marginally better.

[Jeep]

Buying it sealed isn't going to hurt, but what about a "do it yourself" approach? Could the primer be killed? Could sealant harm the powder or burn characteristics if it seeps in past the case head? The .mil uses one product for the primer and another for the case head. Will primer sealer or nail polish work on both?

I've got some top end (and somewhat expensive) self-defense ammo. I don't want to risk destroying it in an effort to make it marginally better.

I wouldn't try sealing already manufactured unsealed ammunition precisely because something could go wrong with the process.

[Hambo]

In my limited testing, (unsealed rounds accidentally going in the washing machine) unsealed rounds have still detonated after being fully submerged.

I test them that way too. My wife returns any ammo that went through the washer (and sometimes the dryer). FWIW it has all fired.

I've also been shooting some of my reloaded rifle and pistol ammo from '92-'94 and it has all been good go. None of it is sealed and it was stored under normal conditions, mas o menos.

Sealed or not, if I dunked ammo in the swamp I'd make sure it was for practice only after that. I've got plenty of good stuff for hunting or carry.

[Odin Bravo One]

By Altitude, I mean a hike up Pike's Peak, especially if it was stored at sea level, or similar........the change in pressure and temperatures is enough, along with condensation to create a concern of moisture. HALO and HAHO jumps also require the sealed necks.

The only time I have ever really had issues, however, is coming from a High Altitude jump, and going into a 1 ATA depth dive in sea water.........unsealed ammo failed 100% when attempted to be shot at sea level following this event.

All of that said, I do not seal my hand loads, with the exception of my precision .300 BLK loads.

[Unobtanium]

By Altitude, I mean a hike up Pike's Peak, especially if it was stored at sea level, or similar........the change in pressure and temperatures is enough, along with condensation to create a concern of moisture. HALO and HAHO jumps also require the sealed necks.

The only time I have ever really had issues, however, is coming from a High Altitude jump, and going into a 1 ATA depth dive in sea water.........unsealed ammo failed 100% when attempted to be shot at sea level following this event.

All of that said, I do not seal my hand loads, with the exception of my precision .300 BLK loads.

Thanks! Unique data-points!

[LSP972]

Buying it sealed isn't going to hurt, but what about a "do it yourself" approach?.

Doable; but if you do the bullets too (assuming you're reloading them), the tedium factor is off the chart. Doing loaded factory ammo on both ends isn't quite so bad.

I do it for my "shower gun" ammunition. The primers are a no-brainer; invert the cartridges in a loading block, put a dollop of lacquer-based nail polish over each primer, let it sit for a few seconds, then wipe the excess clear. The bullet end takes a bit more time, because you don't want any excess lacquer around the case mouth/bullet juncture. Serious tedium here, folks... but if you've got an 8 YOA granddaughter who loves to 'help granddad load burrets', and who has abnormally good dexterity for her age... you're golden.

I've been doing this for years now, with various factory .38 and .357 offerings. I change 'em out every six months, like my carry ammunition, and shoot them in practice. No duds so far. Whether the "sealing" process contributes to that, I couldn't say for sure.

But it makes me feel better...

FWIW, a bloody looonnnggg time ago I did an article on this very topic for Combat Handguns magazine. Virginia Commander was the editor (and still a hammer; that's "attractive", for you Yankees), if that tells you how long ago it was. Basically, I took some .38 rounds, sealed them using the technique described above, then put them in various mediums in baby food jars. I think water, Break-Free, and WD-40 were my "test mediums". I left them to soak for a week, I think it was.

All of the rounds exposed to water fired. Some of the rounds exposed to Break-Free fired. None of the round exposed to WD-40 fired. But that latter was not news, because the dangers of WD-40 around ammunition were well-known by then. Well, by some, anyway...

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