Powder life?
- Thread starter thumper1
- Start date
4 years is not anything to worry about!
Properly stored, most smokeless powder has a shelf life of several decades.
I have a small amount of Norma 205 that is still good.
It was discontinued in the 1960's
Also have about ½ lb of an old bulk batch of H4895, from about 1958 or 9.
Best storage is a cool, dry place where temp remains relatively constant.
Regards, Eagleye.
Properly stored, most smokeless powder has a shelf life of several decades.
I have a small amount of Norma 205 that is still good.
It was discontinued in the 1960's
Also have about ½ lb of an old bulk batch of H4895, from about 1958 or 9.
Best storage is a cool, dry place where temp remains relatively constant.
Regards, Eagleye.
Times 2.
I still have some H4831 that was originally surplussed in the early fifties. They had so much of it left over from WWII and Korea that it was still available in 35/50 pound kegs, right up to the early seventies.
On the other hand, I had some Ammomart #44 powder and some #47N, which was Swedish surplus powder made by Nobel and Bofors.
The #44 was identical to 3031 and the 47N was very similar to Norma MRP or N160.
They were both incredibley consistent powders and I really do miss them both.
The problem with them was they both deteriorated on the shelf through no fault of my own.
They were both good when I bought them from old Tom Higginson but after 10 years or so, they started to give off corrosive gasses and seriously clump together.
I ended up burning 14 pounds #44 and throwing 10 pounds of N47 into the compost, where it would turn into fertilizer.
Just understand, they cost about $4/pound with taxes and free delivery if you bought 21 pounds or more.
I got a group of shooters together and purchased 63 pounds of each. I kept a 21 pound lot of both.
Now, they are sadly gone. They made up the bulk of my powder as well.
I have only had two other powders go bad on me. I had picked them both up at a gun show in Kamloops several years earlier and they did fine. Again, it was about 10 years after purchase that they started to break down. Again, I have no idea how they were stored. I do know I was getting some very inconsistent groups out of it all of a sudden. Upon inspection of the bore the next morning, a fine rust had appeared. That had only happened once before, with the #44 powder and it ruined a very decent Win Mod 70 257 Rob barrel. Needless to say, the barrel was quickly flushed with hot water several times and oiled liberally. It was monitored closely for several weeks after as well. That powder was IMR 4064. The other powder to deteriorate was an IMR product as well, IMR 4320.
All of the cans looked good, no swelling at all but I did notice some rust on the caps. Now, I know better and always inspect the cans for swelling or rust. Any sign of either and I dump the powder.
I have no idea how old the powder were when I bought them. Unless powder prices are at bargain basement levels, I won't buy opened cans, tubs or other containers of powder anymore. It just isn't worth the hassle.
Modern powder stored in cool, dry conditions will last almost forever.
Older types started degrading almost as soon as they were made, with the nitrocellulose molecules breaking down. This in turn rendered the propellant mildly acidic, which accelerated the breakdown. When smokeless powder was still new technology, there were some spectacular accidents in magazines, both on land and in capital ships. The Brits and, I think, the Austrians lost battleships that way and there's been speculation that the USS Maine might have gone the same way. A stabilizer added to modern propellant slows this down to a crawl, but heat will boost the process.
New, cool, 4 years? Good to go.
Older types started degrading almost as soon as they were made, with the nitrocellulose molecules breaking down. This in turn rendered the propellant mildly acidic, which accelerated the breakdown. When smokeless powder was still new technology, there were some spectacular accidents in magazines, both on land and in capital ships. The Brits and, I think, the Austrians lost battleships that way and there's been speculation that the USS Maine might have gone the same way. A stabilizer added to modern propellant slows this down to a crawl, but heat will boost the process.
New, cool, 4 years? Good to go.
The old Hodgdon's surplus powder origially referred to as, "4350 data powder," then changed to H4831, seems to have terrific lasting qualities. Maybe that was partly the reason I chose, "H4831," for my CGN name!
I still have some of the bulk that came from a 25 pound keg in the mid 1960s and could be bought, delivered to centrral BC, by any firm with a wholesale licence, for $18 for the 25 pound keg full.
Just this fall I gave some of it to a grandson for loading in his older Browning A Bolt 30-06. A little later he told me it sure worked well, with some good 180 grain bullets I gave him. He circled a finger and thumb to make a circle and told me it made a group about this size at 200 metres!
A bit after one such bullet made a one shot kill on a good whitetail buck for him.
I am also jealously guarding some Norma 203 and 204. Sadly, my N205 is all gone, but I recently got a can of Norma MRP, which was a replacement for N205.
I still have some of the bulk that came from a 25 pound keg in the mid 1960s and could be bought, delivered to centrral BC, by any firm with a wholesale licence, for $18 for the 25 pound keg full.
Just this fall I gave some of it to a grandson for loading in his older Browning A Bolt 30-06. A little later he told me it sure worked well, with some good 180 grain bullets I gave him. He circled a finger and thumb to make a circle and told me it made a group about this size at 200 metres!
A bit after one such bullet made a one shot kill on a good whitetail buck for him.
I am also jealously guarding some Norma 203 and 204. Sadly, my N205 is all gone, but I recently got a can of Norma MRP, which was a replacement for N205.
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Not sure why it happened but i`ve had two cans of IMR powder go bad when much other older stock stayed okay. All stored in the same cabinet. Both cans were IMR4198 different lot #`s. But cool and dry is your friend for storage.
Like others have mentioned, proper storage helps..... If you open up the powder container, and it has smell to it (like ether - aka starting fluid), I'd be having a good look at it. Sometimes it will have a brown, almost rust coloured surface if it's deteriorated.
I've had some powder deteriorate, to the point where it rusted out the can it was in. Others, stored in the same place for the same duration were fine....
Stan
I've had some powder deteriorate, to the point where it rusted out the can it was in. Others, stored in the same place for the same duration were fine....
Stan
easyrider604
CGN Ultra frequent flyer
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- Greater Vancouver, BC
Based on previous responses, seems like rifle powder is susceptible to deterioration.
I haven't read anyone post about his spoiled pistol/shotgun powders.
Could it be that for some reason, pistol/shotgun (fast/medium) powders are more stable than rifle (slow) powders?
I haven't read anyone post about his spoiled pistol/shotgun powders.
Could it be that for some reason, pistol/shotgun (fast/medium) powders are more stable than rifle (slow) powders?
I cycle through shotgun/pistol much faster than rifle.
I think storage is everything.
I bought at a gun show a can of IMR 4320 and it was completely ruined. Fumes rolled up when I opened the can. I poured some out to look at and what I poured out expanded so much, that it wouldn't all begin to go back in the can.
I just got done using an exact same type of can, with IMR 4320 in it, that I had bought new and that powder was still perfect.
I bought at a gun show a can of IMR 4320 and it was completely ruined. Fumes rolled up when I opened the can. I poured some out to look at and what I poured out expanded so much, that it wouldn't all begin to go back in the can.
I just got done using an exact same type of can, with IMR 4320 in it, that I had bought new and that powder was still perfect.
Can`t say what the problem was with mine, both were imr4198 metal cans. I`ve got some 700x that dates back to the 80`s, 12lb. can with 4-5 left and it`s just fine. Also have some old unique i don`t use anymore and it`s fine. Looks like the guys on this thread all had trouble with imr don`t know if that`s just a coincidence or not.
I found this today on another reloading forum. These are not my words but seems to make sense.
I have been talking to an expert in this field, and I have not totally written my notes up, however
What the manufacturers 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. In the process of combination a nitric acid gas is released. This process is a consequence of the chemical attraction between NG and NC. It cannot be stopped, it will happen, and that is why there are stabilizers in the powder. To slow it down.
Heat accelerates this process. Exposing powder to high temperatures for extended periods of time is bad. The expert said, if you could freeze the powder without introducing water, you could slow the process down. (he said something to the effect that contact with water detoriates powder)
Since that is hard, cool conditions are about the best we can get.
The expert said that powders are initially tested after 10 years. (I think, could have been 20 years). They put a paper in contact with the powder. The paper that changes color if the 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.
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 in the powder can (acid gas eating the can up) and red powder.
So, what about leaving the top off the powder for six months?; probably nothing bad will happen, as long as it did not rain in the can, bugs did get in there, and the can was not left out in 100 F heat for that time period, or left out in the sun. Powder is a polymer and sunlight will damage it, just like it damages paint.
Keep it cool, keep it capped, and check for rust color.
I have been talking to an expert in this field, and I have not totally written my notes up, however
What the manufacturers 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. In the process of combination a nitric acid gas is released. This process is a consequence of the chemical attraction between NG and NC. It cannot be stopped, it will happen, and that is why there are stabilizers in the powder. To slow it down.
Heat accelerates this process. Exposing powder to high temperatures for extended periods of time is bad. The expert said, if you could freeze the powder without introducing water, you could slow the process down. (he said something to the effect that contact with water detoriates powder)
Since that is hard, cool conditions are about the best we can get.
The expert said that powders are initially tested after 10 years. (I think, could have been 20 years). They put a paper in contact with the powder. The paper that changes color if the 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.
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 in the powder can (acid gas eating the can up) and red powder.
So, what about leaving the top off the powder for six months?; probably nothing bad will happen, as long as it did not rain in the can, bugs did get in there, and the can was not left out in 100 F heat for that time period, or left out in the sun. Powder is a polymer and sunlight will damage it, just like it damages paint.
Keep it cool, keep it capped, and check for rust color.
