I've been reloading now for about 38 years. Most of the time I try and load enough rounds to use up a pound of powder. However, if I am just working up a load I might find a powder that I didn't care for, or for some reason I'll end up with 3/4# or so.... I've hated to throw it away. I noticed 3 cans of IMR powder, 4895, 4320, 4350 in the storage area, all nearly 3/4's full.... But it's old and I mean old. The price on one can reads $6.98, lol.... All my powder is kept in a cool, dark, dry area,,,, But when is old, to old.... I've noticed that the powder doesn't have that fresh (ammonia, ether) smell, like a new can.... I know that loaded ammo lasts forever, it seems. But how about powder? Is there a way to tell, from the code on the bottom of the can when it was manufactured and when it should be disposed of?

Signed, Frugal

when powder "goes bad" it takes on a distinct foul odor or becomes "wet" looking.

If the powder has some of the familiar smell and looks like original powder then I'd not hesitate to use it......

Powder can be kept for 30 years as I have some that old.....but, like you, try to use it up in a few years. I've seen wet looking powder but don't know how old it was or what conditions it saw in it's time. It's possible that some powders will deteriorate quickly.....but then it will smell bad and look wet.

As vapodog stated, good powder has a very distinctive smell--sort of a sweet smell. Find a canister of newer powder and compare that smell to the old powder with which you are concerned. They should have a similar smell. Powder that has gone bad will have lost that sweet smell and have taken on a sour odor. Powder keeps for a very long time (over 30 years). Some people are shooting ammo with powder that is over 60 years old. Stored in a cool, dry environment, it will outlive most of us.

Thanks, The cans that I have do not smell as fresh (ammonia, ether, whatever) as they did when they were new, but they also don't smell "sour". The "new" smell just isn't as strong as they were.... I'll try them and see how they do....

quote:

I'll try them and see how they do....

It'll be fine!

I recently have used up some un-opened cans of powder with price tags reading $4.88 for the pound, I think they are 35 years old. These cans have seen temp variations and the canisters have surface rust in a couple places but they are cranking out good shooting consistent loads. One thing I notice is that the powder seems dusty compared to new powder. My old powder is shooting fine. If the cans were rusted through or the powder was clumpy I would never use it.

Try pouring some of the powder. If you get a very fine, sort of "reddish" colored dust that is another indicator that powder is going bad.

Send those three cans to Roger's Powder Disposal Temple City CA. roger

O.K. #1). Powder is made with solvents and if you can smell them, O.K. Alcohol. Ether like starting fluid. Acetone like nail polish remover.

Powder that has "gone bad" has the smell of other organics like vinegar. The other signs are deterioration of the powder itself of chemical attack on the can. Lots of rust.

Powder stored properly, like in conditions where you live, should last "half of forever." Now if it is in temperature extremes and under water, high humidity...

The big problem, Rifleman went into this couple decades back, during the war IMR stick powders usually were washed repeatedly to get the acids out. There was a war on. A couple of wash processes were ignored since the powder was going to be used "right away." The war ended and some of this acidic powder got into surplus distribution. It made the red dust. It smelled of vinegar. It rusted cans fast.

It is full of nitrogen. Makes fair fertilizer. Please don't waste it. Luck.

It smelled like nitric acid and when mixed with water became that and burned my lawn. FACT roger

I am puzzled as to why this topic arises so much ?.


Nitrocellulose deteriorates with time, yielding acidic byproducts. Those byproducts catalyze the further deterioration, increasing its rate. The released heat, in case of bulk storage of the powder, or too large blocks of solid propellant, can cause self-ignition of the material. Single-base nitrocellulose propellants are most susceptible to degradation; double-base and triple-base propellants tend to deteriorate more slowly. To neutralize the decomposition products, which could otherwise cause corrosion of metals of the cartridges and gun barrels, calcium carbonate is added to some formulations.

To prevent buildup of the deterioration products, stabilizers are added. 2-Nitrodiphenylamine is one of the most common stabilizers used. Others are 4-nitrodiphenylamine, N-nitrosodiphenylamine, N-methyl-p-nitroaniline, and diphenylamine. The stabilizers are added in the amount of 0.5-2% of the total amount of the formulation; higher amounts tend to degrade its ballistic properties. The amount of the stabilizer is depleted with time. Propellants in storage should be periodically tested on the remaining amount of stabilizer, as its depletion may lead to autoignition of the propellant.



( Interesting article on particulates of unused and spent powders association ) .

Detecting the use of handguns via the determination of the organic additives in smokeless gunpowder residues (OGSR) presents a promising alternative to primer metal residue analysis. Compositional analysis of the gunpowder additives nitroglycerin, diphenylamine, and ethyl centralite provides information that can associate residue samples with unfired gunpowder. We evaluated the composition of seven reloading smokeless gunpowders, both in bulk and as single particles, by ultrasonic solvent extraction/capillary electrophoresis. Handgun-fired residues obtained from three common weapon calibers loaded with the known reloading powders were compared with the unfired powders. In general, the composition of the residues was similar to that found in the unfired powders. For double-base powders, comparing the ratio of the propellant (P) to the total amount of stabilizer (S) for both residue and gunpowder samples proved to be a useful measurement for identification. This P/S ratio demonstrated that the additives in the residues did not greatly change relative to the unfired powder, providing a useful indicator to aid in forensic powder and residue evaluation.


The properties of the propellant are greatly influenced by the size and shape of its grains. The surface of the grains influences the speed of burning, and the shape influences the surface and its change during burning. By selection of the grain shape it is possible to influence the pressure vs time curve as the propellant burns.

Faster-burning propellants generate higher temperatures and higher pressures, however they also increase the wear of the gun barrels.

A Primex powder contains 0-40% nitroglycerin, 0-10% dibutyl phthalate, 0-10% polyester adipate, 0-5% rosin, 0-5% ethyl acetate, 0.3-1.5% diphenylamine, 0-1.5% N-nitrosodiphenylamine, 0-1.5% 2-nitrodiphenylamine, 0-1.5% potassium nitrate, 0-1.5% potassium sulfate, 0-1.5% tin dioxide, 0.02-1% graphite, and 0-1% calcium carbonate, with nitrocellulose accounting for the remainder.[2]



# Stabilizers, to prevent or slow down self-decomposition

* Diphenylamine
* 2-Nitrodiphenylamine
* 4-nitrodiphenylamine
* N-nitrosodiphenylamine
* N-methyl-p-nitroaniline


N-phenyl-o-nitroaniline, is an organic chemical, a nitrated aromatic amine, a derivate of diphenylamine. Its chemical formula is C12H10N2O2, or C6H5NHC6H4NO2. It is a red crystalline solid, usually in form of flakes or powder, with melting point of 74-76 °C and boiling point of 346 °C. It is polar but hydrophobic. Its CAS number is 119-75-5.

2-Nitrodiphenylamine is used as a stabilizer for synthetic rubbers, explosives, propellants (eg. in Otto fuel II, smokeless powders, in some US Army double-base propellants in solid rockets, and in other applications involving nitric acid esters), plastics, and lubricants. It is also an intermediate for organic synthesis, and a civilian solvent dye.

In some explosives, it is used to control the explosion. One of its major uses is to control the explosion rate of propylene glycol dinitrate.

As a stabilizer, its major role is to eliminate the acidic nitrates and nitrogen oxides produced by gradual decomposition of nitric acid esters, which would otherwise autocatalyze further decomposition. Its amount is usually 1-2% of the mixture; higher amounts than 2% degrade the propellant's ballistic properties. The amount of the stabilizer depletes with time; remaining content of less than 0.5% (with initial 2% content) requires increased surveillance of the munition, with less than 0.2% warranting immediate disposal, as the depletion of the stabilizer may lead to autoignition of the propellant.

As I shall assume not many of you own a Gas Chromatograph -,Mass Spectrometer !?. Then deposing of suspect

propellants too either Roger or I would be an acceptable alternative to you using them !.


In summary ; Some powders deteriorate faster than others , depending on stabilizers and amounts used .

[QUOTE]Originally posted by Doc224/375:
I am puzzled as to why this topic arises so much ?.


You did such a beautiful definitive job and than in one sentance to BURPS!

As I shall assume not many of you own a Gas Chromatograph -,Mass Spectrometer !?. Then deposing of suspect

propellants too either Roger or I would be an acceptable alternative to you using them !.


*** "to" either Roger or "me"*** roger

drop a match in one of those tins, that will tell you if it's good or not. be sure to video tape it and share with us!

seriously though, as others have stated, if it has been kept stable and dry, it will be fine. It might sport lower velocities than a fresh batch but I bet it will go bang when you poke the primers.

Actually Roger; Grammar was never my strong suit as numbers elements calculations

took precedence over that many years ago .

Shouldn't it have read " to either Roger or myself " ?.

Your motto is correct " Talk is cheap it takes money to purchase Whiskey " .

Reminds me of the Indian at the clay pits in that John Wayne movie McClintock .

Wheres the Whiskey wheres the party ?, no whiskey no party ; We go go home now !.