Lesson-Learned: Primer Storage and Humidity

[Cascade Hemi]

Interesting ... but ... not sure how I'd do that since all of my thousands of primers have been stored in exactly the same way. I really don't think there'd be any difference over just a week. My sense is that "years in humidity" could change the dynamic, but not "weeks". You do bring an interesting point to this lively debate. That being ... all these throngs and hordes of people that swear their decades-old and maxi-moist primers always go "Bang" ... really aren't coming to that discussion with data about "how" they go "Bang". Do those old primers deliver the same SD ES Velocity and Accuracy as the new and dry ones. Are they only good for plinking, but not for precision ELR work? I don't know. Maybe someone reading this that has both old-soggy and new-dry primers can do a quick side-by-side test for us that focuses on ballistics and accuracy at distance.

I'm not doing anymore personal observations or shared tests though ... my fragile ego can't handle the criticism.

How long does it take for primers to acclimate? It can't be more than a week or two. Your fragile ego can handle this. You're a good person and people like you, dawgonnit.

 

[sirhrmechanic]

Just an anecdote... because I 'do' store primers in AC/Heated reloading room...

But I have 'trip poppers' set up around grape vines to keep the deer out. Or did when the vines were small. These are basically just shotgun primers with clackers on them. Pull the pin and the primer fires. Deer run away. Works well.

This weekend I was cleaning out my run-in and had 2 stakes (four trip alarms) in my wheelbarrow with the trips still in place, pin in. They have been outside in a run-in through two winters and two summers. Outside. Not in the rain, per-se. But in Vermont 20 below to 95... zero humidity to high humidity. Rain and snow definitely blow into the run-in. But it doesn't exactly get soaked. But it's... outdoors for all purposes.

Decided to see what would happen if I pulled the pin in one of the clackers. Aimed it away from myself (perpindicular as the primers have a habit of launching...) Pulled the pin and boom! Fired. Second one. Boom. Fired. Third one. Boom... all four.

These are Winchester 209 shotshell primers. At least 20 years old because that's when I stopped reloading shotshells. AND sat outside for another 2 years.

So... either 209's are some kind of a miracle primer. Or they are not as sensitive to environment as we might believe.

Be careful!

Cheers,

Sirhr

PS. In conflict archaeology, as on my trip to Monte Cassino in 2019)... grenades are found regularly. When the fuses are removed, they will often fire just fine. After lying outdoors for 70 years. In Combles, France the team unearthed a box of WW1 Potato Mashers from a bunker that had been buried since 1918. They were like new. French EOD took those away. In Lake Champlain about 30 years, ago, tons of Civil War shells were discovered. Dumped after the war. Literally tons. They detonated just fine in a quarry after Army EOD came in and 'picked them up." It was a big boom. Don't assume because of age or storage the chemicals have deteriorated. Maybe no longer match grade. But they will all-too-often go Boom unexpectedly and on the unwary.

 

[Cascade Hemi]

Food for thought, to add to the discussion.... Or something to make your brain hurt.

Would "dehydrated" primers, once loaded into cartridges, draw moisture from the powder in the loaded ammo until some sort of equilibrum is reached? < if they're not used fairly quickly>

Dehydrate both.

 

[Shoots 700's]

store the primers in a stab!e environment and they last year's. I have some left over from the 90's and they shoot just fine.

 

[DeathBeforeDismount]

Yes.. please store high explosives In a sealed metal container. Dry them out nice and good so they get even more unstable whilst In a container that both contains pressure and can be shrapnel.

Keep these great ideas coming.

 

[DeathBeforeDismount]

Just an anecdote... because I 'do' store primers in AC/Heated reloading room...

But I have 'trip poppers' set up around grape vines to keep the deer out. Or did when the vines were small. These are basically just shotgun primers with clackers on them. Pull the pin and the primer fires. Deer run away. Works well.

This weekend I was cleaning out my run-in and had 2 stakes (four trip alarms) in my wheelbarrow with the trips still in place, pin in. They have been outside in a run-in through two winters and two summers. Outside. Not in the rain, per-se. But in Vermont 20 below to 95... zero humidity to high humidity. Rain and snow definitely blow into the run-in. But it doesn't exactly get soaked. But it's... outdoors for all purposes.

Decided to see what would happen if I pulled the pin in one of the clackers. Aimed it away from myself (perpindicular as the primers have a habit of launching...) Pulled the pin and boom! Fired. Second one. Boom. Fired. Third one. Boom... all four.

These are Winchester 209 shotshell primers. At least 20 years old because that's when I stopped reloading shotshells. AND sat outside for another 2 years.

So... either 209's are some kind of a miracle primer. Or they are not as sensitive to environment as we might believe.

Be careful!

Cheers,

Sirhr

PS. In conflict archaeology, as on my trip to Monte Cassino in 2019)... grenades are found regularly. When the fuses are removed, they will often fire just fine. After lying outdoors for 70 years. In Combles, France the team unearthed a box of WW1 Potato Mashers from a bunker that had been buried since 1918. They were like new. French EOD took those away. In Lake Champlain about 30 years, ago, tons of Civil War shells were discovered. Dumped after the war. Literally tons. They detonated just fine in a quarry after Army EOD came in and 'picked them up." It was a big boom. Don't assume because of age or storage the chemicals have deteriorated. Maybe no longer match grade. But they will all-too-often go Boom unexpectedly and on the unwary.

Keep in mind old ordinance does deteriorate. In a former life I helped manage a service branch's small arms collection. We would routinely find items that were demilled but not marked or not demilled correctly. Many explosives will crystallize and get unstable as it ages, which has killed many of old battlefield scavengers and military collectors.

We found a live ww2 jap grenade in the collection. Anacostia EOD wouldn't come out, so we drove it down to quantico where we knew the NCOIC would take anything. They ended up drilling it out underwater and giving back to us so we could put on display. I did get a nice tounge lashing for driving a live grenade through dc in a gsa vic but also got a huge thanks for taking care of it and not shutting out part of the base down for hours waiting for EOD. Looking back I was an idiot for doing this.

Point is, you don't fuck around with old ordinance. Priming compound is highly explosive and by far the most dangerous part of making ammo. It's not uncommon for a primer bunker to blow, killing everyone inside.

Humidity while it effects burn rate and efficiency also provides a saftey buffer. Going below 35-40% is just stupid IMO.

 

[Keeper22]

Why not just use the primers to load ammo, then store ammo? I always use oldest primers first, when reloading. I get having some primers in reserve, but if things go bad, I would rather not have to go load ammo.

 

[Bigfatcock]

WD-40 is the only thing I’ve found that reliably kills primers.

 

[hkguns]

Yes.. please store high explosives In a sealed metal container. Dry them out nice and good so they get even more unstable whilst In a container that both contains pressure and can be shrapnel.

Keep these great ideas coming.

We're not dealing with Nitro and it isn't like they're all in a bag together. That statement is over the top hyperbole.

 

[supercorndogs]

I’m using up 20yr old WLR that sat on a shelf. Had $17.89 price tag! They’re going boom still.

I see the newer ones have blue anvils now. Newer like 2017 probably…

I am finishing a batch of CCI 250's from the 1980s. My dad still uses primers that old and older that have been sitting on shelf in non-climate controlled garage for 40 years. The last batch of CCI 250s I used was from the 1970s.

6 creed ammo loaded with said primers a random charge of h4350, and 105 HPBT in Starline brass.

 

[supercorndogs]

We're not dealing with Nitro and it isn't like they're all in a bag together. That statement is over the top hyperbole.

Putting primers or powder in a sealed metal container, is pretty dumb.

 

[supercorndogs]

Just an anecdote... because I 'do' store primers in AC/Heated reloading room...

But I have 'trip poppers' set up around grape vines to keep the deer out. Or did when the vines were small. These are basically just shotgun primers with clackers on them. Pull the pin and the primer fires. Deer run away. Works well.

This weekend I was cleaning out my run-in and had 2 stakes (four trip alarms) in my wheelbarrow with the trips still in place, pin in. They have been outside in a run-in through two winters and two summers. Outside. Not in the rain, per-se. But in Vermont 20 below to 95... zero humidity to high humidity. Rain and snow definitely blow into the run-in. But it doesn't exactly get soaked. But it's... outdoors for all purposes.

Decided to see what would happen if I pulled the pin in one of the clackers. Aimed it away from myself (perpindicular as the primers have a habit of launching...) Pulled the pin and boom! Fired. Second one. Boom. Fired. Third one. Boom... all four.

These are Winchester 209 shotshell primers. At least 20 years old because that's when I stopped reloading shotshells. AND sat outside for another 2 years.

So... either 209's are some kind of a miracle primer. Or they are not as sensitive to environment as we might believe.

Be careful!

Cheers,

Sirhr

PS. In conflict archaeology, as on my trip to Monte Cassino in 2019)... grenades are found regularly. When the fuses are removed, they will often fire just fine. After lying outdoors for 70 years. In Combles, France the team unearthed a box of WW1 Potato Mashers from a bunker that had been buried since 1918. They were like new. French EOD took those away. In Lake Champlain about 30 years, ago, tons of Civil War shells were discovered. Dumped after the war. Literally tons. They detonated just fine in a quarry after Army EOD came in and 'picked them up." It was a big boom. Don't assume because of age or storage the chemicals have deteriorated. Maybe no longer match grade. But they will all-too-often go Boom unexpectedly and on the unwary.

I will have to ask my dad which shotgun primers, but he got some reloading supplies from a guy with box of shotgun primers ou could tell had been under water. The primers were all covered in rust when he opened them. He tried a few in empty shells just to see if they worked. They did so he loaded some trap loads with the rest of them that also worked.

 

[sirhrmechanic]

I will have to ask my dad which shotgun primers, but he got some reloading supplies from a guy with box of shotgun primers ou could tell had been under water. The primers were all covered in rust when he opened them. He tried a few in empty shells just to see if they worked. They did so he loaded some trap loads with the rest of them that also worked.

And I do t know but could surmise…. Shotgun primers made to work in wet duck blinds in shells with cardboard waxed tubes with only crimps and cardboard/fiber wads… may be better sealed than rifle and pistol primers
For cartridges that are much less sensitive to moisture.

That is pure supposition on my part.

Maybe someone here knows.

Sirhr

 

[Baron23]

View attachment 8122397

Why? Cause there are a good number of absolute utter assholes on this board in addition to the many expert, knowledgeable, helpful, and friendly people that are here.

Dat’s why.

 

[Baron23]

Wait, this is interesting. I think by dehydrating the primers you may change their burn rate. I don't know it to be true though. Can you do a pressure ladder for a caliber you load for and post the results? Maybe the same pressure ladder with primers left on the shelf for a week?

Screw all of these dickheads, I'd like to know how the humidity of primers effects velocity, ES, and SD of known loads. This could be an awesome thread.

Burn rate? Not sure modern primer material burns (conflagration). At least in the past it was high explosive and detonation was caused by a shock wave propagating thru it. So, I’m not at all sure how water content would effect this type of material’s detonation.

Or am I way off base?

 

[morganlamprecht]

one time years ago, i was curious, so i took a couple primed cases and wet tumbled w/ stainless pins for 1 hour...water/dawn/lemishine solution

let them completely dry...and they both still fired lol not sure what it proves, if anything, but i quit worrying about storing them in ambient house conditions after that and havent noticed any ill effects for the past 10-11 yrs

i have seen cases wet tumbled that werent completely dry before loading and it seems to kill the powder, not the primer...once the dud round was pulled apart the clumped up powder inside had flash/burn marks all over it, but it didnt light off

 

[Cascade Hemi]

Burn rate? Not sure modern primer material burns (conflagration). At least in the past it was high explosive and detonation was caused by a shock wave propagating thru it. So, I’m not at all sure how water content would effect this type of material’s detonation.

Or am I way off base?

Splode rate?

 

[spife7980]

Splode rate?

 

[Holliday]

I stumbled across a few articles about storing primers and how humidity affects them over long durations (aka: "years"). I live in Central Oregon, basically High Desert, and I store my primers on the shelf in my reloading room in my house, which is temp and humidity controlled to about 70° and 35% respectively. Historically I figured that was fine, but what I've read lately, and the amount of money I have invested in my 12,000-ish primers, made me re-think that practice.

So I bought a sealed (waterproof) plastic tub for storage, and a batch of little desiccant packages ... and loaded the tub with my primers and threw in a couple of desiccant packs. Within a few days, my desiccant had turned from "orange" to "dark green" indicating they were saturated. I pulled them out, and threw in two more packs and a few days later, same result.

I'll keep doing this until I get desiccant that doesn't saturate, and then ratchet back to a schedule that works to keep my primer stock nice and dry.

Lesson-Learned: Storing primers in a temperature-and-humidity-controlled environment "on a shelf" ... isn't good enough to keep them dry and reliable for years. I needed a sealed container and desiccant packs to guarantee a "bang" instead of a "click" 5-10 years down the road.

Hope this helps someone else that, like me, thought "on a shelf" was the right place for long-term primer storage.

Good thread. Seems lessons were indeed learned if not the ones originally thought….. My primers are in a sealed plastic container, a small amount of desiccant and a bluetooth sensor that tracks temperature and humidity. My Wyoming cottage is not environmentally controlled. We are semi-arid here. Humidity in the tub hovers in the 23% +/- range.



Powder is stored the same way but I use Boveda 49% packs to shoot for an RH of 50%.

Powder is actually more of a concern in this semi-arid climate as it drys over time. This has caused problems in the past with powder that is opened (seal broken) burning faster over time.

 

[straightshooter1]

Good thread. Seems lessons were indeed learned if not the ones originally thought….. My primers are in a sealed plastic container, a small amount of desiccant and a bluetooth sensor that tracks temperature and humidity. My Wyoming cottage is not environmentally controlled. We are semi-arid here. Humidity in the tub hovers in the 23% +/- range.

View attachment 8122961

Powder is stored the same way but I use Boveda 49% packs to shoot for an RH of 50%.

Powder is actually more of a concern in this semi-arid climate as it drys over time. This has caused problems in the past with powder that is opened (seal broken) burning faster over time.

Just an FYI: keep in mind that as powder dries out, the loss of moisture also makes the powder lighter resulting in more powder being loaded when measured by weight. So, burn rate is really just one of the two factors involved.

 

[ma smith]

Just to sanity check a couple things in this thread. I tried to reference sources, but don't simply take my word on it.

1) Powder BENEFITS from humidity controlled storage.
Basic explanation: Humidity alters the 'energy' per unit vol or mass. OEM humidity is ± 50% as a guideline. 90% or 10% relative humidity is not interchangeable with 50% in terms of load performance. For more details, consult an expert. But this is directionally correct info.
See Litz Volume 3, chapter 7.

2) Primers do NOT REQUIRE humidity controlled storage.

Basic explanatinon: Performance is altered by physical-contact with liquid-water (not water vapor or basic humidity). Primers degrade over "high heat", defined as heat over 150F. Basic storage variation from Humidity 20 to 80% or temsp 0 to 100F are not outside the guidelines of normal for primer storage.

Source: SAAMI. This advice has been slightly revised (but not contraditcted) in current publications.
Source: https://saami.org/wp-content/uploads/2022/11/Info-Doc-Primers-11-8-2022.pdf

5. The factory containers in which primers are packaged need only normal conditions of storage.
They should be kept dry and not exposed to high temperatures (more than 150° F). If exposed to
wet conditions or high temperatures, they may deteriorate, yielding misfires or poor ignition of
the propellant powder.

5. (Old Version)

2a) To render primers inert, suggestions are to use eg soapy water or oil (not plain water). This is directionally correct, and consistent with the notion that water-vapour is not alone detrimental to primers. But for more information, again, consult a proper expert. Source: CCI industry publications.> https://www.cci-ammunition.com > F4004_Centerfire_Primers_Caps_Lewiston_SDS_NA_Publication.pdf

Methods for Cleaning Up: DO NOT SWEEP SPILLED PRIMERS INTO A PILE. Spray spilled primers with a water/detergent mixture. Do
not allow primers to become dry. Collect in original trays or submerge in oil.

From SAAMI, they suggest liquid water will risk 'deterioration' but they stop there. Again, YMMV

4. Primers exposed to water or any organic solvent, such as paint thinner, gasoline, kerosene, oil,
or grease, may deteriorate, resulting in misfires or poor ignition.

ETA - disclaimer- I'm not an expert. This is for discussion purposes only. Consult proper experts.

 

[Holliday]

Just an FYI: keep in mind that as powder dries out, the loss of moisture also makes the powder lighter resulting in more powder being loaded when measured by weight. So, burn rate is really just one of the two factors involved.

Exactly, I have mentioned this several times here on the Hide. I was attempting to touch on the subject without adding too much, to avoid highjacking the thread. This information solved some issues I was observing in my real world testing. In particular powder that was falling short of my desired case fill vs. what QL was saying. Keeping my powder from drying out lined things back up.

 

[Holliday]

1) Powder BENEFITS from humidity controlled storage.
Basic explanation: Humidity alters the burn rate. OEM humidity is ± 50% as a guideline. 90% or 10% relative humidity is not interchangeable with 50% in terms of load performance. For more details, consult an expert. But this is directionally correct info.
See Litz Volume 3, chapter 7.

Good stuff. I have purchased a couple of Litz’s books. Great info.

 

[cast1]

That's it ... I'm giving my sealed tub to my wife for kitchen use, throwing away my unused desiccant packets, and putting my primers back on the shelf. If I could figure out how to delete this thread ... I would.

You should eat the desiccants.

 

[rustyinbend]

You should eat the desiccants.

This has been an interesting journey. Feedback falls into basically five camps:

1. I don't care where I store them or for how long, because they always work.
2. Storing them unsealed but in a climate-controlled environment is a solid and convenient strategy.
3. Seal 'em and dehumidify 'em and they'll last forever.
4. I hear all this, but it's devoid of testing so I just don't know what's best.
5. Rusty is a moron for even starting this thread, and he should clearly be kicked out of the forum.

The discussion was good. I feel like I'm landing somewhere between 2 and 3. Maybe 4. But the argument for 1 is compelling. That said, I think a vote for 5 would probably get a majority.

Screw it ... I'm selling all my primers and taking up Basket-Weaving.

 

[Cascade Hemi]

Your primers are all dry and stale, I'll give you $14 but you have to thank me.

 

[morganlamprecht]

i think the test was good...i just think the conclusion/lesson learned might have triggered most of the push back

"isn't good enough to keep them dry and reliable for years. I needed a sealed container and desiccant packs to guarantee a "bang" instead of a "click" 5-10 years down the road."

blanket statements have to be tested/made very carefully on the internet, because it opens the doors for anyone who has experienced otherwise to come barging through it...you did see a difference in the desiccants, but it doesnt necessearily mean the primers wouldnt have worked down the road. That would have to be tested in 10 yrs. Plenty have people have used primers stored for way more than 10 yrs just fine.

Now maybe your stored primers will last for 200 yrs, and on the shelf will only last 100 yrs...but thats a long time commitment test there lol

 

[FredHammer]

An old boy at my gun club wanted to build a clear resin top with various cartridge heads for the bar. Cool idea. Members donated a bunch of different stuff. When it was done it looked awesome, but the story he told getting there was hilarious.

Dude pulled the bullets from donated ammo, poured the powder and soaked the primed cases in penetrating oil for a week. He said when he cut the faces of the case heads off at the extractor groove, everyone of the primers popped off!

So I guess it’s kinda hard to render a primer inert!

 

[rustyinbend]

Your primers are all dry and stale, I'll give you $14 but you have to thank me.

Does that include shipping? After all, there are 12,000 of them. Can we do $20 with shipping included? That's $0.00166 each so it's still a good deal for you. I can throw in a hand priming tool, and later today I'll stop at the 7-11 and pick you up a 6-pack of "Kiss My Ass".

 

[Cascade Hemi]

12k hardly makes it worth it.

Does that include shipping? After all, there are 12,000 of them. Can we do $20 with shipping included? That's $0.00166 each so it's still a good deal for you. I can throw in a hand priming tool, and later today I'll stop at the 7-11 and pick you up a 6-pack of "Kiss My Ass".

 

[Holliday]

This has been an interesting journey. Feedback falls into basically five camps:

1. I don't care where I store them or for how long, because they always work.
2. Storing them unsealed but in a climate-controlled environment is a solid and convenient strategy.
3. Seal 'em and dehumidify 'em and they'll last forever.
4. I hear all this, but it's devoid of testing so I just don't know what's best.
5. Rusty is a moron for even starting this thread, and he should clearly be kicked out of the forum.

The discussion was good. I feel like I'm landing somewhere between 2 and 3. Maybe 4. But the argument for 1 is compelling. That said, I think a vote for 5 would probably get a majority.

Screw it ... I'm selling all my primers and taking up Basket-Weaving.

Welcome to the Hide. Primer discussion ranges from “ah fuck it” to “here buy a $600 priming tool to set them within .0000000001” because it matters to God”.

With all that, I feel a reasonable compromise is a sealed container at 23% +/- . I never tell other people they need to do that. Maybe this thread will cause me to reevaluate and maybe not.

Quite frankly, I would bet that it is the fluctuations in humidity and temperature that are more the problem. This was my main concern.

 

[redbullitt]

I found the thread useful. Carry on OP.

 

[secondofangle2]

I'm in the middle ground about this. Last year I bought this:

And put some in used glass jars with small holes (too small for egress) punched in the metal lids. Can be reactivated in the oven when it turns blue (must have cobalt in it I'm guessing).

I put those glass jars in my non-sealed plastic bins with my primers to prevent *excess* moisture from accumulating.

I may not have done this but for 2 reasons: 2000 RWS 50 BMG primers that are hard as hell to get and now worth $1 or more each; and I had some reloading equipment (Redding and RCBS dies) rust in my garage, so when I got my $1200 prazipress and $2500 WTC 50 BMG die, I decided to cover it with a plastic cover and put the above linked moisture absorber jars in there to prevent the Prazipress and WTC dies and other high dollar stuff from rusting. So I had leftover dessicant, and it went in with the primers.

I also now add 49% humidity packs to my powder jugs, but that's a different story

 

[rustyinbend]

Waited 5 days in a sealed tub ... Desiccant went from bright orange to dark green.
Put in new packets and waited another 5 days ... Desiccant went from bright orange to medium green.
Put in new packets and waited 5 more days (to today) ... Desiccant went from bright orange to medium orange.
I'll check in a week, and probably replace the packets and go into a once a month replacement mode.

• Overkill? Probably.
• Unnecessary? Likely.
• Harmful? Unlikely.
• Annoying to many on this thread? Hopefully.
• Good therapy to test my memory once a month? Definitely.

Here's today's results:

 

[Holliday]

Waited 5 days in a sealed tub ... Desiccant went from bright orange to dark green.
Put in new packets and waited another 5 days ... Desiccant went from bright orange to medium green.
Put in new packets and waited 5 more days (to today) ... Desiccant went from bright orange to medium orange.
I'll check in a week, and probably replace the packets and go into a once a month replacement mode.

• Overkill? Probably.
• Unnecessary? Likely.
• Harmful? Unlikely.
• Annoying to many on this thread? Hopefully.
• Good therapy to test my memory once a month? Definitely.

Here's today's results:

View attachment 8124390

That is a small amount of desiccant vs a large amount of cardboard. It’s not a wonder the packs are turning purple fast.

 

[secondofangle2]

Yeah, he needs the gallon size I linked above if he wants to dry them out too fast and make them go boom

(JK, I highly doubt you can use dessicant to dry out primers "too much" or that doing so makes them unstable, else we would have heard the tales of mayhem aplenty)

 

[Holliday]

Yeah, he needs the gallon size I linked above if he wants to dry them out too fast and make them go boom

(JK, I highly doubt you can use dessicant to dry out primers "too much" or that doing so makes them unstable, else we would have heard the tales of mayhem aplenty)

For that container I would think a couple cups would more than suffice. There must be a formula somewhere. With humidity, I find there is an amount to establish the point you want then a lesser amount to maintain it.

 

[918v]

I’m shooting 30 year old primers stored inside the house. No issues. Primers are waterproof.

 

[Haney]

I’m shooting 30 year old primers stored inside the house. No issues. Primers are waterproof.

Primers are not Waterproof .Many tests prove that you are wrong . A sealant adds water resistance , it does not make them waterProof . Unis Ginex claims they have the best compounds and sealants . They have tested side by side with CCI,Fed, etc . . They held up the longest, but still not waterproof .

 

[bax]

Off Topic ... maybe

"mayhem aplenty"

Wasn't there a dancer who went by that name?

 

[Bugholes]

Rusty-
let me share this with you, and you do with it what you will.
this information came from my tour of the Federal Cartridge plant in Anoka, MN. The person giving us the tour was an employee of Federal and is a friend of mine. He was also, at one time, in charge of primer production at that plant. We toured the entire plant, including the primer production portion of the plant. This was a pretty big deal as I was told they would not allow tours in this area- it was kind of an insider deal. The primer area was remarkable. The priming compound was made and handled wet, in a Humidity controlled room, 99% or similar. There was water on the floor and everything was wet. Primers were filled volumetrically with a scraper of sorts, very interesting. I did see the concrete underground bunkers for primer compound storage That someone previously mentioned (from the outside only).

Here’s the takeaways I got from my friend (who took us on the tour):
-moisture content is critical in the production, usage, and storage of primers (and powder)
-the primers are dried to the desired moisture content before leaving the plant
-the best storage method would be to maintain the same moisture content of the primers as delivered

so what this means to me, is that they should not be stored with desiccant. They should be wrapped, boxed, or stored in a method that inhibits them picking up OR giving up additional moisture. Obviously storage conditions in AZ may not be the same as FL due to humidity. I think it’s safe to say that almost any climate controlled area suitable for long term human occupancy should be acceptable for primer storage. That being said, I store mine inside sealed containers to minimize the moisture change, as recommended by someone who knows more about this then most of us do

 

[secondofangle2]

Off Topic ... maybe

"mayhem aplenty"

Wasn't there a dancer who went by that name?

Dunno, I thought I made it up

 

[Doom]

Food for thought, to add to the discussion.... Or something to make your brain hurt.

Would "dehydrated" primers, once loaded into cartridges, draw moisture from the powder in the loaded ammo until some sort of equilibrum is reached? < if they're not used fairly quickly>

There is a lot of information on the internet. Some is down right wrong, some is correct and misapplied, and sometime it is correct. Primers made of fulminate of mercury (corrosive) do degrade over time and storage is important. Lead styfpnate on the other hand is very stable and non hydroscopic (does not take on or release moisture). Storage requirments related to humidity are basically non condensing, ie do let it get wet. So no, Dibbs, it would not draw moisture from the air or from the powder.

Both powder and primers are handled and processed in humidity controlled environments to prevent the build up static electricity for prevent an electrical spark from creating detonation or combustion.

 

[secondofangle2]

The voice of reason has arrived

 

[Rocketvapor]

Ran a test several years ago on deactivating primers.
Oil, transmission fluid soaked and washed and dried.
Soaked in water, dried in air, went bang.
Dot 4 brake fluid and vinegar dissolved the compound. Cups were clean.

 

[Doom]

Ran a test several years ago on deactivating primers.
Oil, transmission fluid soaked and washed and dried.
Soaked in water, dried in air, went bang.
Dot 4 brake fluid and vinegar dissolved the compound. Cups were clean.

I have tried penetrating oil, WD-40, WATER. Once dried BANG!

 

[Cascade Hemi]

Once dried BANG!

De...hydrated?

 

[Doom]

De...hydrated?

After about a week just sitting on the bench I crushed them between to two bricks. As I recall I let the oil and WD40 sit for a week, poured the oil out and waited a week. Put the water in a quart freezer bag for a week. took them out and waited a week, then did the brick thing. I was trying to kill them. My conclusion was you can't reliably kill a primer with those methods. Now I just put them in junk brass and shoot them.

 

[232593]

Wait, this is interesting. I think by dehydrating the primers you may change their burn rate. I don't know it to be true though. Can you do a pressure ladder for a caliber you load for and post the results? Maybe the same pressure ladder with primers left on the shelf for a week?

Screw all of these dickheads, I'd like to know how the humidity of primers effects velocity, ES, and SD of known loads. This could be an awesome thread.

In Southern AZ the humidity is very low for 9 months out of the year. 9-12% typically. However during monsoon season it gets up to 30-40%. I have not seen any difference in my loads due to effects of humidity on primers.

Now, stick powder and humidity is a whole different story.

 

[232593]

Just one other consideration given the humidity content of some powders when new and ammunition manufactured with them that can sit for many decades and still shoot just fine.
I think the bigger problem is what happens to a bullet sitting in the neck of that brass over the years welding its self in place if not laquer sealed like milspec ammo.

Tested that the other week with a factory .408 round. In pulling the bullet I damn near ripped the base of the case. Copper Solids seem to have this issue more than lead core bullets