imr 4895 powder ?

[rebs]

I have a 1 lb can of imr4895 powder that I have had since the mid 1970's. Would this powder still be good ? I want to reload some 300 Savage rounds with 155 gr HPBT bullets wioth the starting load of 36.0 gr.

[AlaskaMike]

If you do a search here about powder going bad you'll find a lot of good suggestions.

About the easiest one I can think of is to pour a little bit onto a sheet of white paper. If you see nothing but the black powder granules you should be fine. However, if you also see a fine reddish powder, then that's a dead giveaway that the powder's gone bad.

Mike

[44 AMP]

I remember a story in a gun book from back in the 70s, called "4895 25 years later".

basically, the author bought 100lbs of 4895 (4 25lb caddies) sometime shortly after the end of WWII. He used up three of them over the years, but the 4th one wound up getting stored in his parents barn (in Pennsylvania!) until he "found" it, 25 years later.

He worked up his loads again with the old powder, and found that the old 4895 was exactly like the new stuff, except for delivering velocity approx. 100fps less, for the same charge weight.

If you see anything like "rust" (reddish powder) in the gunpowder, it is degrading. If it SMELLS different than it should, it is degrading. If there is any kind of crystal formation around the lid, it is not only degrading, but highly DANGEROUS (not common with the chemicals in gunpowder, but possible)

Basically, modern gunpowder is very stable, and has a long shelf life. Possibly longer than you or I do, under good conditions.

What is really amazing is Black Powder. While less stable to handle than smokeless powder, black powder has proven to be stable enough to last over 100years. There has been more than one instance of the discovery of a firearm that was loaded in the Civil War era, still loaded today, and which fired normally when tested.

[rebs]

it smells fine and I did the white poaper test and there is nothing but black. I am going to load 5 rounds with the starting load and see how it shoots.

[serf 'rett]

^That's what I would do.

Coworker gave me three pounds of 25+ year old W-231. Worked fine.

[243winxb]

The metal can may produce some rust. The powder itself may still be fine. Its not always easy to tell. Some IMR 4198 i have has the dust from a rusty can. Its shooting OK. This IMR 4895 powder didnt look that bad after it was out of the can. Smell seemed Ok. But i scrapped it. [IMG][/IMG] [IMG][/IMG] [IMG][/IMG] Click photos for larger view.

[Clark]

My jugs of 1960s bulk grade military pull down 4895 is still good, but it never acted like IMR4895 canister. It always acted like H322 canister.

[csmsss]

I'd argue that any storage conditions that resulted in the formation of rust like that on the outside of the can couldn't possibly have been any good for the contents inside, most particularly if the canister has been opened. I personally wouldn't use any powder from a can that looked like those in the images above.

[Slamfire]

You are on the edge of a normal shelf life. The rule of thumb for safe storage of gunpowder is 45 years for single base and 20 years for double base. Early in the last century the storage lifetime of smokeless powders was considered to be 20 years or less:

Army Ordnance Magazine, June 1931, page 445 :

“Smokeless powder constitutes one of the greatest hazards from a storage standpoint, due to the fact that it is subject to deterioration and at the best cannot be expected to have a life greater than about twenty years…….Master samples of all lots of smokeless powder are under constant observation in the laboratories at Picatinny Arsenal. Should any of these samples indicate rapid deterioration, notification is given at once, and steps are taken to use this deteriorating material within a very short period, if possible, or else withdraw it from service.”

Sometimes gunpowder goes bad well before 45 years:

http://thefiringline.com/forums/showthread.php?t=472369

4895 gone bad?
________________________________________
I just opened a one pound can of IMR 4895, stamped E91 on the bottom (1991?) L7867. The can was sealed and stored in a cool, dry basement room. I immediately noticed a significant amount of fine brown dust throughout the power. It left a notable brown dust type substance on my power funnel, and I decided not to use it. I asked a friend and he has had the same thing (not sure if its actually the same stuff) in some 4831. I could just toss it out to play safe, but this stuff isn't that cheap anymore.

Heat is the worst enemy of gunpowder, the hotter it is, the faster gunpowder deteriorates:

Table extracted from data in

Surveillance and in-service proof - the United Nations

http://www.un.org/disarmament/convar...Proof(V.1).pdf





All estimates without a chemical analysis of the percentage of stabilizer left in the gunpowder are going to be crude at best. So for the home reloader, if the powder has turned red, or smells like acid, it is way beyond its safe limits. If in shooting this powder you get unexpected sticky extraction at loads below maximum, that could be an indication the powder has gone bad. Old gunpowder does not burn evenly and will pressure spike.

[jepp2]

Slamfire is right. I have an 8 pound caddy of IMR 4895 from the late 60's and the powder is just fine. Very light rust on the inside of the metal can. Strong solvent odor, and nothing but black on the white paper.

I also had a 1 pound can of IMR 4350 that I bought in 1991 and stored in the same conditions as the 4895. I noticed a lot of red dust when I loaded some 280 rounds a couple of years ago. The inside of the can had fairly heavy rust. But the powder still had the solvent smell. This year I shot a few of the rounds loaded with this powder. Despite being a mid pressure load, there were signs of high pressure and the velocities were much higher than the book projected. I stopped firing and pulled the bullets on the rest of the loads. The remainder of the can and the powder from the pulled loads went on the lawn.

[rebs]

The can I have has no rust on it, it looks like a new can,

[Slamfire]

The can I have has no rust on it, it looks like a new can,

That is good. Hard to believe there are no rust spots inside. I have 1990's IMR 4064 with little rust spots in the cans. Red rust in cans is due to nitric acid gas which forms when powder deteriorates. Nitric acid gas attacks metals, brass will crack after exposure.

I have shot 60's IMR 4350, it shot well. I shot 60's Bullseye, it shot well. I had to toss half of the surplus IMR 4895 I bought as it went bad. Since I learned about the kinetics of gunpowder, I am no longer buying estate sale powder from the 80's or earlier.