I've got some powder and primers that are going on 7 years old. I just got back into reloading for my 460wby mag and wanted to be sure that it was ok to use my old powder and primers.

Umm 50+ years?
Unless the powder "smells funny" or shows signs of clumping/deterating it's fine.
Primers, unless you store them underwater or in solvents, will last just about forever.

I think I have some powder and primers in my inventory that is less than 7 years old, but I wouldn't think of using it 'cause it ain't "cured" good yet.

Some of my very BEST performing powder is my dwindling stock of Surplus 4831, which has to be over 60 years old as of now. Similarly, I have some primers purchase right before the 1968 GCA went into effect; they go "bang" just like any other primer.

quote:

Originally posted by Tailgunner:
Umm 50+ years?
Unless the powder "smells funny" or shows signs of clumping/deterating it's fine.
Primers, unless you store them underwater or in solvents, will last just about forever.

Sounds about right!!!!

7yrs is some of my YOUNG powder. As stonecreek said I let mine cure longer than that.

quote:

Originally posted by ramrod340:
7yrs is some of my YOUNG powder. As stonecreek said I let mine cure longer than that.

quote:

I think I have some powder and primers in my inventory that is less than 7 years old, but I wouldn't think of using it 'cause it ain't "cured" good yet.

Some of my very BEST performing powder is my dwindling stock of Surplus 4831, which has to be over 60 years old as of now. Similarly, I have some primers purchase right before the 1968 GCA went into effect; they go "bang" just like any other primer.

Me too.

But I have a cure for you two. Start shooting more!

quote:

But I have a cure for you two. Start shooting more

Well while I have to agree with your thought process seems like I've ended up with several rifles that overlap. Then I ended up with good quantity of powder per rifle to unsure I had the same lott of powder and don't have to work up new loads.

That said I have several others that go through several pounds of powder a year.

So I have some rifles that burn their share of "green" powder and a few that really liked the aged stuff.

I'm with ya.

I have some that just sit there waiting to draw a tag!

I have some IMR 3031 in a narrow metal can that has some rust on the lid that I was given by a friend who had it for several years and had bought it from a gun show and the powder was some of the oldest at the gun show. So, I have no idea how old it is, but I'm sure its more than 7 years old. IT STILL WORKS GREAT IN MY 30-30!

I have fired ammo from just after WW I. 7 Mauser with the round nosed bullets. If stored reasonably and used within its limits, life should be about indefinite. Flooded basement? someone's shed out back? Bet's off. If in house where people live... Probably last longer than I.

Had a gunsmith friend who picked up a .45 ACP revolver and was showing me. He opened the cylinder and I saw ammo in the cylinder (for home protection) dated '18. Gray case. I asked if that wasn't pushing it and he said he wasn't worried. So I hit him up for one for my collection... His father had been a 'smith and he had tons of "old" stuff...

At the same time, if you are trying to put them into one hole for competition... Then you might want the newer stuff for greater consistency, although I wonder about that. Gov. match ammo used corrosive primers into the '50's, supposedly more consistent that non corrosive primers??? Luck.

quote:

Originally posted by Chefrific:
I've got some powder and primers that are going on 7 years old. I just got back into reloading for my 460wby mag and wanted to be sure that it was ok to use my old powder and primers.

Powder and primers are too old when you pull the trigger and here the "click"

I've shot a lot of WWII 8x57 ammo without one miss fire. Some of it was dated as early as 1939. roger

Note that only the very young think 7 year old powder and primers are "old."

I have access to a gentleman who is an energetics expert. I asked him about smokeless powder lifetime. The whole topic is a subset of “Insensitive Munitions”. A term you can Google and find bits and pieces in the public domain.

Smokeless propellants are used in more applications that just cartridges. Rocket motors, explosive warheads, these all use smokeless propellants.

He told me that powder starts deteriorating the day it leaves the powder mill. The rate of deterioration of double based powders is governed by the Arrhenius equation. http://en.wikipedia.org/wiki/Arrhenius_equation. The hotter it is, the faster it goes. Single based powders apparently deteriorate in a linear fashion.

What the expert told me was that double base powders are made of nitroglycerine (NG) and nitrocellulose (NC). The NG wants to wick its way, through capillary action, into the NC. Forming a lower energy state compound. In the process of combination nitric acid gas is released. As nature wants to go to a lower energy state, this reaction is inevitable. There are preventive stabilizers in the powder which eat up the nitric acid. The stabilizers get consumed over time.

Exposing powder to high temperatures for extended periods of time is bad. Heat accelerates the reduction-oxidation process.

Cool dry storage conditions, he actually said “artic”, are about the best for long term storage of powder.

The expert said that Navy powders are initially tested at 10 years. They put a litmus paper in contact with the powder. If the paper changes color, nitric gas is present.

If the paper shows a problem, they then chemically test the powder for the amount of stabilizer in the powder. If that drops below 20% original, than the powder is scrapped. You have to have the original powder records to know how much stabilizer was in the powder when it was made.

The Army scraps by clock time. Double based powders are scrapped at 20 years, single based 45 years.

A few years ago TALON released tons of demilled military powders. That stuff was at the end of its service life. Half of my surplus 4895 powders went bad. One keg turned red and was outgassing and it was poured out on the lawn. About 8 pounds did not turn red, but went bad in the case.

First indications that I had a problem were that I had a lot of split case necks on fired cartridges. Then case necks started to crack on unfired ammunition. When I pulled bullets, I smelt nothing, in the case or in the bottle, but I found green corrosion on the bottom of bullets. I believe that nitric acid was weakening the work hardened areas of the case, and causing corrosion on the bottom of the bullets.

Incidentally, the powder shot exceptionally well in cases that did not have case neck cracks. I shot some exceptional scores with the stuff at 600 yards with 168 Match bullets. I had "funny" retorts on some rounds. The expert said as the surface of gun powder changes, burn rates are affected.

When the burn rate has been changed, you can have pressure spikes due to irregular ignition. Also, old double based powder has a sensitized surface due to nitroglycerine migration to the surface. This will spike initial burn rate even though the nitroglycerine/ nitrocellulose content of the powder has decreased in time. This may have caused a few blowups with old surplus ammunition.

If the powder changes color, it is bad. It is grossly bad. It was bad a long time before the color changed. And it is time to pour it out. That is when you typically see red rust in a metal powder can (acid gas eating the can up) and red powder.

I was told that when enough nitric acid is released, the powder will spontaneously combust. The expert diagramed the chemical reaction and hot spots can develop as energy is released. As the Military is extremely scandal sensitive, they won’t tell anyone that big bunkers have blown up, but they have. Ammunition depots go Kaboom all the time due to old ammunition spontaneously combusting. You can Google this and find incident reports in the literature. But you won’t find mention of some of the American ammunition incidents that this expert investigated. We Googled one incident he wrote a report on and found nothing in the public domain.

Government Rule #2: Minimize Scandal.

Water is bad for smokeless gun powders as it damages the powder surface and wicks NG to the surface. Even through age is reducing the total energy content of the powder , wicking NG to the surface will increase the initial burn rate of the propellant, which has lead to pressure spikes.

Contact with rust is bad for powders. As I understand contact with iron oxide increases the rate of the reduction-oxidation reaction.

The Navy used to store cannon powder in pools but the powder was to be recycled. I guess the water absorbed the nitric acid and kept everything cool, preventing heat build up. But the expert told me that the dry lifetime of powder is rapidly reduced after exposure to water.

Primers evidentially have an indefinite shelf life. Assuming the primers were not baked in an oven, soaked in penetrating oil, or the cups corroded, primers will outlast powder.

Some references on the web


www.dtic.mil/dticasd/sbir/sbir031/n154.doc



http://www.almc.army.mil/alog/...pellant_stab_eq.html

quote:

Originally posted by Blacktailer:

Powder and primers are too old when you pull the trigger and here the "click"

They're getting a "little" tired when you hear the "click" before "the boom".