Home Forums Hunting & Shooting Ask The Gunwriters First Sign of Bad Powder

I use H-4895 powder quite a bit. Today I pulled out an old can of IMR-4895 to do a comparison test. The bottom of the can had my notation that I had purchased it in October of 1998.

The powder smelled okay and looked normal. That is, until I poured it through my plastic funnel into the clear plastic tube of my RCBS powder dispenser.

Note the tell-tale stain of super-fine "Cinnamon powder" on the white plastic funnel in the picture below:



When I poured the powder back out of the dispenser, the colored dust stuck to the inside of the clear plastic powder reservoir of the dispenser, shown in the picture below:



This powder has just started going bad. With the passing of time the amount of colored dust will increase rather dramatically to the point that pouring even a small amount of powder out of the can will produce a colored cloud of fine reddish dust. As powder continues to deteriorate it can become unstable and potentially dangerous.

I am pouring the remainder of this can out into the garden. In over forty years I believe this is only the second or third can of powder I have had go bad, so it doesn't happen very often. Occasionally campfire members ask how to tell if powder is going bad, so I took these pictures to share.

Thanks. Nice to know what to watch for.
I had a friend give me some reloading supplies that had been stored in a garage in San Diego since the mid 80's.
I was surprised that after 30 years in those conditions the powder was still good and all the primers still went bang.

Had some 296 eat a metal can here recently . The fine red baby powder inside seemed to never quit coming outta that can .

I inherited a case of IMR 4895 in metal cans. I don't know how old it was. Some of the cans left a little bit of residue like in your photos. I loaded ammo and shot it with this powder. Everything worked normally. Other cans smelled definitely sour when opened. I threw this powder on the garden.

I have some other powder which I am pretty sure is older than the above powder and which shows no sign of deterioration. Also, I recently opened up some 30-40 Krag factory loads from the 1930s and the powder inside seemed normal.

Good thing powder has a long shelf life given the prices we pay.

This is from a previous thread discussing useful life of smokeless powder, for anyone that missed it. Denton provided a link to an extremely educational article regarding smokeless powder deterioration.


"Denton,
http://forums.thecmp.org/showthread.php?t=157820

Thank you for that LINK. It is extremely educational and I recommend it to all shooters and reloaders.

The idea that powder and ammunition will last indefinitely in a good storage environment is absolutely false. There seems to be no sure way to predict.

Deterioration of powder, no matter how slow, begins on day one. A takeaway from that link is that the experts consider all powder over about 20 years old to be suspect. Federal declares a safe shelf life of ten years for their ammunition. If one assumes that Federal is being very conservative and you double their shelf life figure you still wind up at 20 years.

(I have had two cans of IMR powder that were purchased in 1998 go bad. One went bad in just a couple of years. This latest can to go bad is 18 years old.)

According to the link the military keeps samples of the powder used in all their ammo and artillery shells and monitors it for years as to the rate of deterioration. When they estimate a lot of powder has three years of safe life left they put out a notice that the ammo with that powder has to be used up or destroyed by the three-year end date.

Extreme heat is shown to deteriorate powder very quickly. I wonder if this has been a problem for our military in the extreme heat of the Middle East?

I had heard that when the Marines or Army puts on a "mad minute" demonstration that much of the ammo used is old and needs be used up. I have heard this explanation when someone questioned whether the "mad minute" exercise was a big waste of taxpayer money.

I bought a 200 pound keg of WC powder in the 90s.

It was circa 70s. I won't store that much powder in my house.

Its not cool at all in TX 9 monhts of the year.

That powder, at last check was still able to provide sub moa groups in a couple of guns we own that we use it in today...

Doesn't mean next time I head out for another 8 pound draw, I won't be unhappy...

Apparently some powder will last over 100 years, while another batch can go bad in only a couple of years. There are one or more steps in the powder manufacturing process that, if mishandled, can greatly reduce the shelf life of powder.

I have shot the IMR powders with the brown dust with no problems.Has the same MV as powder with out the dust.

The cinnamon dust is nature's way of telling us it is time to dispose of that batch of powder.

This is what one of the scientists said in Denton"s link:

"From what I had read on the internet, which is a repeat of what is said in gun magazines, powder has an “indefinite” shelf life. I think we all remember reading statements to the effect that powder lost energy as it got old, making it essentially benign. This information is not only wrong, it will get people hurt."

"As gunpowder gets older it does not get safer to shoot. Old gunpowder will, and has, blown up firearms. The basic reason is something called “burn rate instability”.

For all your cartridges you want a nice and smooth pressure curve. If the burn rate is irregular, because the nitrocellulose powder grain breaks down irregularly, there will be peaks and valleys instead of a smooth pressure curve. These irregularities can interact in such a way that pressures spike. Double based powders are a combination of nitroglycerine (NG) and nitrocellulose, the NG is there for an energy boost, but unfortunately NG causes a new set of problems.

NG is apparently not bound to the powder grain but is a liquid and it migrates. NG is wicked to the surface of the powder grain over time, one causal reason, water condensing and evaporating on the powder grain surface. Apparently the evaporating water molecules pull on the NG. I was told that created a NG rich surface.

So, even though the total energy of the grain has decreased due to breakdown, the surface is NG rich and that will spike the initial burn rate. Another thing NG does is accelerate the breakdown of the base nitrocellulose molecule by attacking the double bonds holding the NO molecules. Unfortunately all ionic compounds attack those double bonds, water is a main offender because it is always in air, is a polar covalent ion (acts like an ionic compound) and thus you know the reason you were told to store gunpowder in a cold and dry environment.

Quality ammunition is manufactured in humidity controlled environments, between 40% and 20% humidity, but they don't go lower due to electro static discharge concerns."


Other comments from the link:

"Please dispose of (old, decomposing) powder and ammo supply before it starts to get warm or self-heat (via autocatalytic exothermic reaction)."

"Heat accelerates the deterioration/decomposition of powder and the rate is directly proportional to the Arrhenius equation, which is an exponential function. Maybe this is a simpler way to say it: the lifetime of ammunition decreases exponentially as temperature rises."

"Lessons learned -
(1) Ammo (and bulk powder) has a finite shelf life
(2) Ammo (and bulk powder) can be dangerous."

I have never had any go bad.

I was given some old H4831. It came out of a paint thinner can and was put in a plastic jug. I loaded some in a 7MM Remington magnum very mildly for a midrange deer and target load. It turned out to be pretty accurate so I loaded 20 rounds and didn't shoot them for 5 months. The first two I fired seemed ok but the next two showed high pressure so I tore the shells down to find that the powder had corroded the insides of the cases and somehow really got the bullets bonded to the case necks, pulling them was tough. I had to stir the powder with a piece of wire to get it to pour out. After I gave the powder back and three weeks later the guy opens the container some smoke issues forth, he sets it outside wherein it shortly self ignited into a hot flame. This powder had no odd odor or dust in it.

Self ignited ??

I believe you BUT I've never heard of that ! !

Maybe the method of storage ? ? Any ideas ?

Jerry

I bought 3 unopened metal cans of IMR 4320 at a garage sale, same lot no. Opened and used them one at a time, and the middle one exhibited the rust colored dust while the other two were fine. The bad one got dumped.

The original price was on the cans....$7.95. I paid $10 each for them!

That is interesting, in all my years of shooting I have never seen bad powder as anything I didn't buy and store myself goes on the lawn.


Thanks for that.

added, one would think that I would have run up against bad powder in this hot miserable clime, but I haven't.

I just had 4 duds in a box of Rem. 243's dated 1985. They showed corrosion around the bullet and primer. The other 16 seemed fine when my daughter shot them. Another recent thread blamed this on bad powder. These thing have been in a bedroom in the house since I bought them new, not perfect conditions, but probably better than average.

Had a one lb can of imr 4350 that was opened and not needed for years. When next needed I noticed a red dust and posted to this forum if I should be concerned. Most said yes, dispose of, although it still smelled fantastic. It's the only powder I've ever had an issue with. I just used the last of a 30 year old 5lb can of SR 7625 that was still fantastic. And am about to finish off an old 5lb can of SR 4756 that looks equally fantastic.

Some die an early death, some don't. By the way, all have been stored inside my home.

I have a friend who we visited 3 or 4 times a week. Wife and I went to his house one Saturday evening for supper. I noticed his plastic garbage can was melting and hollered for him to come and help put out the fire. We got it extinguished and he told me he had a pound of powder, 4895 if IRC, going bad and he put it in the can. Best not to keep bad powder, for it will definitely self ignite.

I have had a few cans of the IMR in the steel cans go bad recently and several which are still fine. I went back and looked through my records and I think I found something in common. The cans which are still good I bought from a local store which has a real store front in town. The cans which went bad, I bought from a guy who ran a shop out of his basement in his house. I guess the storage before we get the powder has alot to do with how long it lasts.

The guy I got it from said he got it in an ammo can. Picked it up at an estate sale.