Storing powder

[Pdyson]

It will be fine in the garage regardless of humidity. The powder will remain stable in the sealed container till you open the bottle and expose it to the air. Even after opening it would take some time before anything changed. I found a lost cache of powder I bought in the late 80s and 90s. 4 partially full metal cans of IMR 4831, 4064, & 4350 this powder had been stored in a hotter than hell Laredo Texas attic for over 17 years temp swings between 35 and 145-degrees humid for 5 to 95. It was still as fresh and sweet smelling as any of the fresh cans I had in the house. This was back in 2014 before the recent powder shortage and so I poured it out. Had I known what was going to happen, I would have kept and used it.
It might be overkill, but If you reload in the house and store in the garage you might not want to open an ice cold bottle in a warm room. Let it acclimatize a for several hours before opening.
I bought a 2nd hygrometer like the one in my gun safe and put it on my reloading bench. If it's real high humidity, I put off reloading that day. Or I'll just do a small quick batch, pouring only what I need and keeping the bottle closed tight. Whatever you do, NEVER ever leave powder in the powder measure. bottle it back up and seal it tight. Also keeps you from forgetting what powder is in there.
getting too dry is just as bad as too humid. I've read humidity around 40-55% Is ideal and what the manufacturers try to produce. If your powder gets dried out you can throw in a cigar humidor humidity pack to bring it back up. I've never tried it but YouTuber Johnny's Reloading Bench did some tests a couple years ago. They come in several different humidity levels. Look it up it's worth watching.

 

[hseII]

Yes, and Silica packs will help with moisturize/humidity. I store mine in a closet with silica packs.

If you have a fireproof safe, be careful, just because its fireproof, it doesnt mean its also moisture proof. Fireproof safes absorb moisture, so you will need to air it out every 2 to 4 weeks, and keep baking soda and/or silica packs in there as well.

What about a golden rod in a safe that is secured in a manor so the powder won't get near the golden rod?

 

[RidgeTop]

When you open a stored can of powder look for tan smoke coming from the container. A slight amount is o.k. Next smell the contents - if it is sweet smelling it is good. An acrid smell and it gets spread on the lawn for fertilizer.
When you have high temps like Skip's 95deg, I would say don't stock up on powder or primers so you don't risk the chance of them going bad.

 

[Muddyboots]

From Hodgdon:
Smokeless Propellant

The main ingredient of smokeless propellant, comprising from about 55% to 90% of the composition, is nitrocellulose. The process of creating nitrocellulose leaves remnant acid in the material. This acid immediately starts decomposing the finished product. Left alone the decomposition will reach the stage where the propellant becomes unstable and self-ignites. This process resulted in massive explosions at U.S. Government arsenals after World War I.

To increase the life of the smokeless propellant, a stabilizing chemical is used. This "stabilizer" reacts with the acid to slow down the decomposition process. However, as the stabilizer reacts with the acid it is consumed. After the stabilizer is totally consumed, the propellant is no longer protected from the internal acid.

The entire stabilizer / decomposition process is a time and temperature function – the higher the temperature, the shorter the safe life of the powder. Even moderate temperature, over extended time, leads to propellant decomposition. As a rule of thumb, any temperature over that which is comfortable to a person is accelerating the decomposition of smokeless propellants.

Under proper storage, modern smokeless powder can last for decades. However, this does not mean the reloader can ignore how the powder is stored, particularly if in an uncontrolled environment such as a garage or storage building.

 

[RidgeTop]

pdyson, too low humidity is an environment that is conducive to static electricity. Down to 5% or 10% needs caution. I have a grounded pad (like computer techs work on) I reload on and am sure to watch what I wear in the reloading room - some fabrics and shoe soles are notorious for static.

 

[Muddyboots]

SAAMI: Smokeless Powder: Properties and Storage:

Good resource for storage.

https://saami.org/wp-content/uploads/2018/04/Info-Doc-Smokeless-Powder.pdf

 

[Muddyboots]

pdyson, too low humidity is an environment that is conducive to static electricity. Down to 5% or 10% needs caution. I have a grounded pad (like computer techs work on) I reload on and am sure to watch what I wear in the reloading room - some fabrics and shoe soles are notorious for static.

Especially critical for primers. If humidity is too low, static in air, I would not load or handle primers regardless of grounding. The risk is too great for oh crap ignition. Static is prob worse risk for reloaders so gotta be careful.

 

[Varmint Hunter]

Just put the cans in a box and toss them in the bottom of your closet. Presumably, your living quarters does not experience extremes in temperature or humidity. Problem solved and it won't cost you a cent.

 

[LVJ76]

What about a golden rod in a safe that is secured in a manor so the powder won't get near the golden rod?

Never used one, but my understanding is that a rod generates heat to remove moisture in the air, if I am incorrect please feel free to let me know.

How hot will them temperature in the safe be with the rord? And would this temperature be safe for the powder?

 

[Varmint Hunter]

Never used one, but my understanding is that a rod generates heat to remove moisture in the air, if I am incorrect please feel free to let me know.

How hot will them temperature in the safe be with the rord? And would this temperature be safe for the powder?

Golden rods get warm to the touch. They cause air to circulate as the air around them tends to rise. A safe door should be loose enough to allow the slightly warmed air to escape. My Browning safe has many locking bolts but the door is designed to breath. Only in a fire is the gasket supposed to swell up and seal the door.

 

[Hawkeye Pierce]

Eva-dry rechargeable desiccant dryers.
Cheap, efficient and easy. Use a container that has rubber seal and check it every month or so.

 

[LVJ76]

Golden rods get warm to the touch. They cause air to circulate as the air around them tends to rise. A safe door should be loose enough to allow the slightly warmed air to escape. My Browning safe has many locking bolts but the door is designed to breath. Only in a fire is the gasket supposed to swell up and seal the door.

Thanks Sir, appreciate the info.

 

[Petey308]

I throw a 49% Boveda pack in my kegs to keep the humidity regulated on the open ones. It works great.

 

[Varmint Hunter]

I have all of my components in the basement where I reload. Because of the humidity, I run two dehumidifiers 24/7 until the season changes and the heat comes on. The dehumidifiers have automatic discharge pumps and empty themselves through a 1/4 flexible hose that runs into a slop sink. The hose could also be run through a small hole and outside if desirable.