Powder Storage Question - Summer Heat

[gf99-99]

Hi All,

Kind of a strange question but my brother randomly noticed that I store some of my larger 4lbs tubs in the garage (I admit have a reloading component hoarding disorder plus I shoot ALOT of competitive skeet and sporting clays so I use much larger quantities of powder than the average person) and asked if the heat is dangerous.

I have kept powder in the garage for years with no issues but... I never actually thought of it or knew the answer. So figured I would reach out on here and see what others thoughts are. Also note that I am located in AZ and in the middle of summer it can get pretty toasting.

 

[RockAndSage]

A lot of that will depend on how long you're storing it in your garage, and what the max temperatures are. And, whether or not the containers are sealed, or have been partially used.

 

[ScreamingPotato]

I'm curious to follow along and see if it changes the properties or degrades it in any way.

For storage I store mine in the big safe anyway, just in case there's a fire in the house.

 

[gf99-99]

A lot of that will depend on how long you're storing it in your garage, and what the max temperatures are. And, whether or not the containers are sealed, or have been partially used.

Well this summer there were several 115 days in AZ so its pretty hot. All are sealed new (but lets be honest is that little paper seal really sealing anything? The crappy Hodgdon really comes to mind) I would say most have spent 1 summer maybe 2 at the most in the garage. I do use a fair amount of powder so I try and cycle through it, but at the same time I do keep a very large stock on hand for the next powder shortage.

I guess worst case I just bring it all inside the house (its alot!) however the major issue and I mean MAJOR issue with that is we all know what kind of speech I am going to get from the "boss". For those that do not have a house in AZ basements are non existent and I am not fortunate enough to have a whole man cave dedicated room. So a huge rack full of powder jugs apparently does not go well with the house decor and also apparently I should not have all those "bottles of chemicals in the house, they belong in the garage"

 

[rayporter]

from powder valley;

see number 4.

HOW TO STORE RELOADING POWDER​

Home / Reloading Ammo for Beginners & Reloading Basics / How to Store Reloading Powder
Knowing the best way to store reloading powder can help ensure your own safety and keep your powder preserved and effective over the long term. Get the most out of your ammo reloading supplies with these helpful fundamentals.
10 Tips for Reloading Powder Storage
Here are some basic powder storage guidelines for reloaders:

1. Never store containers of powder on the floor – otherwise, you risk moisture contamination or infestation from rodents or insects.
2. Store the powder in the original container if at all possible – powder manufacturers use metal or plastic receptacles that are designed for long-term use.
3. Give the original container an added level of protection by storing it in a plastic box or case – a portable tote protected by a watertight O-ring is a good choice for this purpose.
4. Never keep powder in an outdoor storage shed or garage – these areas can become extremely hot during the summer. Remember, your powder should stay cool at all times.
5. Minimize atmospheric moisture – many reloaders set up their workbench in their basement or cellar. This is fine, but keep in mind that these areas are known for being dank and moist. You may want to use a dehumidifier to keep the air as dry as possible.
6. Never store combustible liquids, explosives, or pressurized sprays near your powder – keep products like gasoline, kerosene, lamp oil, fireworks, and petroleum-based lubricants away from your powder.
7. Avoid storing large amounts of powder in a single container – it’s better to keep smaller amounts of powder stored in separate containers.
8. Make sure your storage area is neat and tidy – clean up water or chemical spills right away, empty trash cans on a regular basis, and keep your workspace free of clutter and potential trip hazards.
9. Limit access to your storage area – consider locking the door to your reloading workshop or asking family members to stay away from it when it’s not in use.
10. Never have an open flame nearby when working

 

[Vern400]

I've had a bottle of H380 go bad over a summer in a. Outside building. It stank and smelled badly. I have had a jug of Blue Dot get questionable. All my old loads are suddenly over pressure. I am still using it but I had to reduce my 20 gauge loads by 1.5 grains to get the book velocity. I noticed that my shotgun was throwing empty shells more than 15 ft so I ran it across a chronograph and the velocity was 1350. The book load was 1,250 ft per second with 7/8 ounces of shot. Now I suspect that I have possibly dangerous Magnum pistol loads I made with the same powder some years back and I have to chronograph a few of those too. I think the nitrocellulose and nitroglycerin are separating in the flakes and changing the burn rate. This is known to be higher risk in the double base powders.

If I had any powder, in Arizona, I would store it in the coolest place in my house that was available which also had very small temperature swings. Even if you store your powder at 70°, you don't really want it to go down to zero and back up to 70 frequently. Cool, and stable temperatures. You shouldn't have a problem with humidity but that's certainly something to consider as well. Below 70% is probably fine.

Yes, you can definitely degrade your powder. The damage will start out as slightly changed burn rate, possibly subtle changes in group sizes and ES, etc.

I accidentally left two packs of 100 CCI large rifle primers in my barn shop for two summers. They were in a ziplock bag with a desiccant pack, but the temperature got to them I guess and I had a few misfires. Failed to fire. I used them up with trail Boss on some subsonic plinker loads. That's the only pack of primers I've left in summer heat for an extended period, and it is the first time I've ever had a large rifle primer failed to fire out of probably 6,000 used