Humidity and reloading

[jonnefudge]

Hi!
Whats your opinion on how air humidity effects primers and powders. I left some cci 200 primers packs in my humid garage for a couple of months (80%). Any suggestions on what to do? The powder cans seems tight enough to withstand the humidity.

/Jonne

[LE-28]

I doubt it hurt them much but it may have had some effect on them. Water won't hurt primers in the long run, I would just put them in the house for a month and dry out what little moisture is in them.
Primers are made under water to stop any chance of explosions, then they are dried out before we get them.
They are usually sprayed with a lacquer sealer to help keep them dry after their dried out. That helps keep humidity from effecting them.

[RC20]

I was given a load of primers that had water damage on the case

They all shot fine. I did put them in a tray to let them dry out if any, but I suspect not.

Reality is primers are damned hard to kill

[briandg]

Primers are coated, they should not absorb water, especially if it's only humid air.

Powder is almost impervious to water.

[T. O'Heir]

Humidity won't bother primers. It'll only bother powder in opened cans. Unopened cans are moisture sealed.

[hounddawg]

what about the bullets, will they rust ? j/k ing

[hdwhit]

jonnefudge wrote:
I left some cci 200 primers packs in my humid garage for a couple of months (80%). Any suggestions on what to do?

I had CCI 400, 450 and BR4 primers that were purchased in 1982 or 1983 and stored in my garage in Northern Arkansas or later, Northern Texas until last year.

They have all worked fine so far.

So, if I can get away with storing primers in a garage for 34/35 years, I don't think you have to worry about a few months.

[hdwhit]

hounddawg wrote:
what about the bullets, will they rust ?

No.

"Rust" is a phenomenon predominately of ferric metals, so unless the bullet has a steel jacket that is not plated or varnished, it will not "rust"

Any metal can be oxidized leading to corrosion. But in the case of the lead and guilding metal most bullets are made out of, this corrosion will not progress fast enough to cause anything other than cosmetic problems. What you have to worry about with decades old ammunition is that as to powder deteriorates acids will form that damage the bullet and case.

[DaleA]

what about the bullets, will they rust ? j/k ing

I probably should NOT try to explain other folks' posts as that can sometimes lead to even MORE confusion but in this case I think the 'j/k ing' in hounddawg's post was short for 'just kidding'.

[hounddawg]

j/k ing is standard internet shorthand for joking or just kidding, sorry if I caused any confusion

[Don P]

A point to ponder, gun powder, primers, bullets, and case are shipped by truck and those trucks are NOT refrigerated. Thy go from a controlled environment to a hot truck, cold truck depending on time of year to a delivery point controlled environment, then to us either in retail or back on a truck hot or cold again from internet sales into our hands. They work when I get them.

[Unclenick]

Primers are pretty well immune to a lot of things. Both the Navy and Norma have done powder cooking experiments and can deteriorate it badly with heat at about 140°F, but it still takes a year or two staying at that temperature. Primers seem unaffected by it.

Humidity and powder do interact, though. Norma's manual shows that powder stored in 80% RH burns about 12% slower than the same lot stored at near 0% RH. They also show that even the powder in a loaded cartridge gradually assumes the environmental humidity level over a period of about a year. I expect something similar for powders stored in containers that have been opened. The reason it happens is that water molecules are the smallest molecules known. At about 0.275 nanometers, they are about 300 times smaller than the polished surface finish on of a mirror. Most of us don't get our brass that smooth in the necks and most of us don't screw a lid on tight enough to weld it to the container. Now you know why the military likes sealants.

In addition, modern powders are sold in plastic jars rather than metal tins. Plastic is not nearly as long-term moisture-proof as metal. All plastic resins have finite water permeation rates you can look up, so eventually moisture gets through them, whether coming or going. Imperfect lid sealing probably allows rather more. So eventually the powder reaches moisture equilibrium with the environment you store it in, even in a closed or sealed container. Only the old soldered hermetic military ammunition tins stood a chance of holding ammunition to a constant humidity level.

[hdwhit]

hounddawg wrote:
sorry if I caused any confusion

No problem.

From your prior posts I was pretty sure you weren't so ignorant as to really think bullets (or cartridges) would "rust", but it gave me the opportunity to play the straight man and point out 1) corrosion in copper alloy generally proceeds so slowly as to not be a problem, and 2) the concern with old ammunition is powder deterioration, not corrosion.