Approximate life span of powder if stored correctly

[Kenk]

Question on powder longevity; from what I can tell, most modern powders will last a very long time, even after being opened. I store my powder canisters in a cool dry environment, as well as away from the sun light...Thoughts?
Thanks


Ken

[sqlbullet]

I don't know how old you are, but I can reasonably assume you are over 21.  Chances are you will die before the powder becomes unsafe/unstable/unusable.

Know the smell of good powder.  Like spoiled meat, bad powder will instantly be apparent by smell.

When in doubt throw it out.

[Kenk]

Thanks man!

[woods_walker]

Yes, I agree with the "cool, dark place" suggestion.

My powders get stored in my basement in what is nominally called a "fruit room" around here. Concrete floor, walls and ceiling, and lack of HVAC ducts make for a nearly steady temp level that is ideal for longterm storage of bushels of potatoes, onions, etc. For my purposes it is ideal for File cabinets with semi-important documents, heirloom photo collections from our families, and secure storage for powder, primers, and the bulk of our loaded ammo stash.

Thanks to the packrats and hoarders (LOL) who were my father and grandfather, I have a tin of RSQ pistol powder, unopened, and nearly 2 pounds of a rifle powder called Sharpshooter. The RSQ may be from around 1900, the Sharpshooter is from the late 1940's.
I pull out the Sharpshooter on occasion and load up half a dozen rounds to entertain friends and grandkids. You know that really "unique" smell of the smoke from Unique loads? Sharpshooter is like that and even more "unique" in it's odor. The only data I ever found in my father's loading records was for .45-70. By interpolation I have come up with a load for .45-120 also. This powder is around 80 years old and still works just like the can of powder I bought at Sportsman's last week.

The RSQ on the other hand...

I have no data for it though I think, with a bit of effort, I could find firearms historians or collectors who could come up with something. But then again, I don't think I would ever try it. The "Cool" factor of a 120 year old unopened can of gunpowder is very fun!

[Kenk]

Thanks sqlbullet,
Upon additional research, it sounds like many powders will last almost indefinitely. If it is stored properly, and does not have a rusty appearance / smell horrible, it is likely just fine...and yes, 21 years of age was a long time ago, hence I am 59 years young 😀

Ken

[Rooster41]

What do you consider "properly stored"? About 30 years ago my ol' man dabbled in loading for his 357 Mag. He used Blue Dot powder and bought an 8 pound can of it. Fast forward to October 2017. My ol' man's house burnt down. While going through the rubble we found this can of powder. It is still about 3/4 full. It didn't smell any different than the stuff I had at home. I have been using it without any problems. Im not sure where he had it in the house and neither does he or what it was stored in but it survived. He thought he left it with his buddy when he decided not to load anymore.

[The_Shadow]

I still have some ammo that I loaded back in the1978/79, I tested some against some new loads and the old was only 8 fps slower than the new stuff.    But we can see that much difference between the same powder loads...

Cool, dry and resealing the container between uses, goes a long ways to its longevity!  I only place enough in my hopper that gets loaded, I can always add if needed or return the powder back into its proper container if not used.

A co worker gave me a one gallon glass jug of powder back in the 80"s it was a stick powder which was said to have been fairly old when it was given to him.  It smelled very good of the solvents and showed no deterioration at all.  I didn't have a positive ID of the powder at the time, but after I studied it and compared it to known samples, I tested it as what I determined to IMR4831.  It proved to be what it was as per testing various loads.   

My brother-in-laws (two of them) lost their homes to tidal surge from Hurricane Katrina, the 9mm stuff (500 rounds) under water and mud for a week or so, I washed, cleaned and dried them.  Only one of those didn't go off.  Pulled it the powder was good the primer was dead.  The other B-I-L brought me some stuff I loaded back in the 80 and some things he purchased.  The cases were showing corrosion, however the factory rounds had nasty powder that would not or barely burn when lit with a match...The loads I loaded had good dry powder inside despite the corrosion on the outside that was considerably less than the factory stuff.  It may have been a result of residual case sizing lube...

Anyway taking care of your powder goes a long ways in its life span!

[Kenk]

Thanks Wade!

[Graybeard]

My reloading room is in my basement with it's own dehumidifier. I have powders I've opened many times, in their original containers that are at least 20 years old. No problems with them at all. Loaded centerfire ammo seems to do just as well if properly stored. Recently fired some Vietnam era .308 surplus ammo that worked just fine. The only ammo I've ever had fail due to age was .22lr. I can only assume that the bullet to case mouth seal wasn't that great and some humidity got inside.

[tommac919]

Just another note to add to the many;

Powder from my Dad ( 2400 ) still going strong after opened numerous time since about mid '60s.  No diff I can see in the few 44 mag rounds I load.

As to older bullets... still shooting WW2 ammo and it never fails to go off ( 45, m1 carbine, and 30-06 )

It outlive him and will prob me too.

[blaster]

powder (and ammo) is definitely more durable than people think!  my powder (as well as reloading components & ammo) is stored in my down stairs ground level work shop under the exact opposite conditions they recommend. its hot & humid all the time. hurricane Irma put 4 ft. of sea water under my house. my loaded ammo is stored in G.I. ammo cans. some of it & their cans, have been under water 3 times over the years from hurricanes Georges, Wilma and Irma.  my powder is on a shelf in a steel cabinet but was still under about 2 ft. of water. all the powder is fine. one opened container of Blue Dot seemed like it wanted to clump up but still shot fine. I also have military surplus ammo from WWII that shoots as good as it did in 1945. corrosive primers and all.

[Trapper6L]

Don't know if this is true or not but I got this from a gunshop owner. The IMR powders you buy today are draw downs from WWII powders. Hodgdon, who now owns the IMR nameplate, keeps the powder wrapped in waxed containers in a pond. It keeps the powder from oxidizing since air can't get to it and the water keeps it cool. Supposedly it'll keep forever like that. I guess the oldest powder I have that I still use is SR4759. I ran into a salvage place that had gotten a full case of half pound cans. That's 24 cans of it. I bought it all for 10 bucks. That was back in the early 1980's. I'm down to the last 3 cans of it and it still shoots great. Like everybody else, it's kept indoors in a cool dry place where no light gets to it. Now that I think of it, I have a couple of cans of IMR4831 that have lids with closeable air vents. Those were from a gunshop in San Antonio named Ad Topperweins on Cincinnati Street. They had bought a large drum of it and packaged it in the WWII surplus cans they had. That powder is still good too. The price tag is still on the cans-$1.98 a pound. Still have some Bullseye in the Hercules can that snaps on. I don't load Bullseye but the can is neat. Gee I have a lot of old crap!

[woods_walker]

Don't know if this is true or not but I got this from a gunshop owner. The IMR powders you buy today are draw downs from WWII powders. Hodgdon, who now owns the IMR nameplate, keeps the powder wrapped in waxed containers in a pond. It keeps the powder from oxidizing since air can't get to it and the water keeps it cool. Supposedly it'll keep forever like that. I guess the oldest powder I have that I still use is SR4759. I ran into a salvage place that had gotten a full case of half pound cans. That's 24 cans of it. I bought it all for 10 bucks. That was back in the early 1980's. I'm down to the last 3 cans of it and it still shoots great. Like everybody else, it's kept indoors in a cool dry place where no light gets to it. Now that I think of it, I have a couple of cans of IMR4831 that have lids with closeable air vents. Those were from a gunshop in San Antonio named Ad Topperweins on Cincinnati Street. They had bought a large drum of it and packaged it in the WWII surplus cans they had. That powder is still good too. The price tag is still on the cans-$1.98 a pound. Still have some Bullseye in the Hercules can that snaps on. I don't load Bullseye but the can is neat. Gee I have a lot of old crap!

Trapper,

This is a big topic you brought up but here's a couple thoughts...(if you're lucky, one of the smart people like The_Shadow will discuss this at length. It's very interesting)

Pretty much all of the WW2 surplus powders had been sold off by the early to mid 70's. Bruce Hodgdon actually bought railroad boxcars to hold the tonnage of surplus powder he bought from the government. IMR is a manufacturer of powder- they used to be under the corporate umbrella of DuPont. Hodgdon was a distributor, not a manufacturer- IIRC, their powders were primarily manufactured by Nobel but they have used several others over the years. Hodgdon NOW is a gunpowder manufacturer since the acquisition of IMR powder, Olin Corporation, as well as Winchester powder name rights.
  Hodgdon originally sold his powders in a funny way. He sold 150# barrels to dealers. The dealers then had to find adequate containers to put it in. You wanted a pound of H4831? You might get it in a brown paper bag. You want 3#? You might get a Hellman's mayo jar or a pickle jar! Years later he had his own pre-printed paper bags, and eventually he moved to metal cans. 25 years ago or so, private citizens could even buy it in 24#(?) kegs.

Anyway, Hodgdon then and now does not use a pond to store powder. I can only imagine what the EPA would say about that! Either IMR or Winchester keeps a very large glass jar in their lab. This jar has smokeless powder that is over 100 years old. There is nothing in the jar but powder and water. Every few years, chemists take a measured sample from the jar and analyze it, the load some in shells and test-fire it.

So far, there is no change in the quality of the powder from when it was freshly made!

[Popeye212]

When I started loading in the 70's I was using WWII H4831