Mix old powder with new...??

[buck460XVR]

You don't get a ballistic heads up. The stabilizer holds down the rate of deterioration to very small numbers until it is used up, and then the powder quickly deteriorates. That's the reason the stabilizers were developed. The military wanted to be able to stockpile munitions for decades without statistically significant ballistic performance changes. They want stockpiled artillery shells to land in the same place new ones do. Same with small arms ballistics. So, the concern with mixing old and new powder would be that you mix the stuff together and all is well for several months or even a year or three, then one day you open the jar to deterioration signs that you had no clue were about to come on.

The main enemy of powder is temperature.

The reason for stabilizers is quite obvious and also quite simple. The reason there are stabilizers in today's modern powders meant for sale to handloaders is identical to what the military wanted. Powder to last over a extended length of time while producing identical performance over that period of time. Before one needs a so called "Ballistic" heads up, one gets a sign of deterioration. This is something for the most part that is quite obvious when powder is still in the canister. Would I mix obviously deteriorated powder with fresh powder in hopes of saving those few ounces? No. But I certainly wouldn't be afraid to mix a powder with a intended shelf life of 30-40 years, that is only 7-8 years old with the same powder that is fresh from the factory, as long as neither showed signs of deterioration and had been properly stored.

Again, while powder deterioration should be a concern for Handloaders, IMHO, it is something that is not readily encountered and when it is encountered is readily identified. This statement from SAAMI and it's published info on "Smokeless Powders, properties and storage" seems to mirror my opinion....

Although modern smokeless powders contain stabilizers and are basically free from deterioration under proper storage conditions, safe practices require a recognition of the signs of deterioration and
its possible effects.

One can read the whole statement here.....www.saami.org/.../SAAMI_ITEM_200-Smokeless_Powder.pdf

From your own statements, since one gets no "ballistic heads up", it seems the suggestion to load the remaining powder and shoot those rounds, would be considerably more dangerous than mixing the extremely small amount of older powder with new powder with fresh stabilizers. Any small amount of deterioration and thus different burn rate would be neutralized by the large volume of the new powder without a real risk of contamination. Many of us that use powder throwers would experience a greater rate of contamination or risk from it, by not using some form of solvent to clean the interior of the thrower between the use of different powders and powders of different age.

Again, most of us handloaders do not hold a doctor's degree in Chemistry, nor do we need to. What we do need is to establish safe reloading practices, which includes proper powder storage and how to recognize deteriorated powder. This is just common sense and something just as many folks with that Doctor's degree are missing than those without one.

As for the heat thing. Yes, extreme heat is a enemy of smokeless powders. But for most modern handloaders, extreme heat is not a real threat. In the study in your link, the temp they used to deteriorate the stabilizers was a constant 100 degrees C, or 212 degrees F. This is the boiling point of water. Very few of us experience this ever in the areas we reload in or store our power, much less experience it for a extended period of time.

There are folks that will mix various lots of the same powder too and folks that warn vehemently against it. Since most modern powders are mixed at the factory to ensure consistent burn rate, I feel safe doing it myself. This does not mean I tell others to. They need to use their common sense and weigh the risk. Same goes for using handloads for SD/HD. Yep.....guess how I feel about that?

 

[Metal god]

How else can you explain two such beautiful yet widely separate groups???

haha hmm has this ever happened to me ?

I was having a hard time during one stretch of load development of having very inconsistent at the time what seemed like on everything . Oh man this drove me crazy for like 6 months . The thing is I did not notice the double grouping at first . It did not happen every time and in that 6 month period I was doing some big time load development and I kept getting inconsistent results . I'd find a charge that shot well only to find out next time out it shot like garbage . This went on for quite awhile until the day I shot this group

Well that's a ten shot "DOUBLE" group with each shot being fired about 30sec apart resulting in two separate sub moa groups . When I saw that target I knew something was wrong and dove down the rabbit hole to figure out what could have been going wrong .

The first thing I did was go back and look at other load development targets I had . I keep all my targets with there corresponding data sheets in binders for future reference . Thank goodness I did because I found a interesting pattern when I looked at the whole of my targets for that last 6 months .

What I noticed was a number of double groups .

With some not being as noticeable as others but still there when you know what you're looking for

And that's just the targets I took pictures of . So first I check the scope and put it on another rifle . Scope worked just fine . Then I think , maybe my reloads are consistently inconsistent err wait-what ??? never mind , so that leaves the shooter . How ever although I can shoot pretty good I just did not see how I could some how consistently have two different holds on the rifle during the same string .

This led me to start a thread either here at TFL or elsewhere . Regardless the first couple reply's were check the scope then one guy said that looks like your action screws are loose During all that testing and trying to figure out what was wrong I never once check my action screws . In fact until that moment I had never torqued my action to any specific poundage .

When I check the action screws with my torque driver ( this is from memory ) but think my front screw was 20lbs and my back one was 5lbs . This was a Savage model 10 with accustock so I called Savage and asked the torque recommendations and was told 40lb on each . I ultimately did a torque test shooting multiple groups at different torque settings and settled on 35lb in the front and 30lbs in back with loc-tite on the screws .

I've not shot a double group since .

 

[Sure Shot Mc Gee]

If there's years of un-capping and re-capping a jug of powder under different humidity conditions. Why contaminate so much new with so little of the old.
"Sounds like a: Hillary would do."

 

[FLChinook]

WOW!

A number of you suggested checking the action screws but I've always ignored this idea (in my unbelievable ignorance). After all, my Weatherby came to me new from the factory and SURELY Weatherby knows how to torque an action screw... Apparently not! Or else mine loosened a lot since leaving the factory.

Another reason is that my nit-picky brain abhors burred rifle screws...

But Metal god showed pictures (Thanks!) and demonstrated very similar targets. I had to try. Here's what I found (turns are approximate, say +/- 5-deg):

Torque: 10-15-20-25-30-35 (35 in-lb is Weatherby's max for wood stock)
Rear Screw total turn (deg): 0-20-35-45-75-110
Front Screw total turn (deg): 0-2-10-25-45-75

The front screw was tighter but both moved quite a bit as the torque increased.

I can't wait to get back to the range!

 

[Slamfire]

I smell some confirmation bias:

Although modern smokeless powders are basically free from deterioration under proper storage conditions, safe practices require a recognition of the signs of deterioration and its possible effects.

Now if that were 100% true, then why in the next paragraph are they giving people advice on how to detect gunpowder that has gone bad?
http://www.alliantpowder.com/getting_started/safety/storage_handling.aspx

Powder deterioration can be checked by opening the cap on the container and smelling the contents. Powder undergoing deterioration has an irritating acidic odor. (Don't confuse this with common solvent odors such as alcohol, ether and acetone.)

Check to make certain that powder is not exposed to extreme heat as this may cause deterioration. Such exposure produces an acidity which accelerates further reaction and has been known, because of the heat generated by the reaction, to cause spontaneous combustion.

Never salvage powder from old cartridges and do not attempt to blend salvaged powder with new powder. Don't accumulate old powder stocks.
The best way to dispose of deteriorated smokeless powder is to burn it out in the open at an isolated location in small shallow piles (not over 1" deep). The quantity burned in any one pile should never exceed one pound. Use an ignition train of slow burning combustible material so that the person may retreat to a safe distance before powder is ignited.

Why would they warn about out accumulating old powder stocks? Maybe they belong to the Organization to reduce clutter in the house? Clutter is the bane of society, a terrible illness that well all must try to eliminate. Or maybe they know the stuff will auto combust at some point?

These are pictures of WW2 era powder hoards. The owners of this stuff are likely to die in flames when these kegs burn the house around them.

Ever since I learned about powder going bad I regularly sniff my gunpowder. I break the seal and check. Just last week, when I was reloading for my 35 Whelen, I sniffed this powder and it was bitter. I went around the house smelling chemicals to find something with a similar smell. The base smell was like ammonia. However , it was more bitter than ammonia, more like red pepper in the nose. I poured this 1999 powder out. It was not fuming red nitric acid gas, but, I know from previous experience, old gunpowder will ruin cases in months.

I have two kegs of 1998 N140, popped the seals and both smelt "sweet". I have no idea why the 1999 stuff has gone bad, but lots of Vihtavuori powder from the mid nineties is turning sour right now.

Take a look at the pictures in this post:

Has anyone else had Vihtavuori N140 corrode in loaded ammo?

http://www.falfiles.com/forums/showthread.php?p=3745264

I believe much of the irrationality about shelf life on gunpowders comes from those who believe I am immortal and so is all of my stuff! . Well sorry, you and your gunpowder have a "best buy" date. And, at some unknown point in the future, you and your gunpowder stash will be dust. While that point is currently unknown, it is fixed, and you will get there.

Given that the lifetime of gunpowder is unpredictable, I consider it best practice not to mix different lots, especially lots that are years or decades old. In fact, based on all the powder I have had to toss because it went bad, I am going to say, shoot up your oldest powder, make a point of using it up in ten years, don't expect anything to last 20 years. But if you have 20 + year old gunpowder, shoot it up.

 

[Unclenick]

Good post.

Whoever wrote the SAAMI piece was trying to do a public service, but was not a precise technical person. The page also states, for example, that powder contains enough oxygen to burn completely. Nitrocellulose combustion is actually oxygen deficient, which is why carbon is left in your bore instead of it all becoming CO or CO2 gas.

The suggestion powder should be stable in the right conditions for decades is based on bulk powder. You buy a train-carload of powder in a single lot and, barring a process error, it will, indeed, last for decades under good storage conditions. But it will also have a burn rate that typically wanders 15% or so from one lot to the next (board member Hummer70 said that during his years as a test director at Aberdeen there was one lot of powder that was off 30% from nominal in burn rate, but that the most extreme example he'd seen, with 20% being the next highest). A 10% charge reduction doesn't cover it a burn rate change as wide as can occur in bulk powder, which is why you need a pressure test gun to determine loads with it.

The canister grade powder sold for reloading has to have its bulk grade parent lot tested for burn rate at the powder plant and then adjusted by the plant to bring it within the tighter limits needed for published data to be reasonably valid for it. Hodgdon says they use control to ±3% for their Australian powders and ±5% for IMR powders. Those are probably as much as the particular plants can achieve at reasonable cost.

The way they adjust the burn rate, as I mentioned before, is by blending with held-back prior lots that were unusually fast or slow. You get a new lot that is too fast and you blend it with enough of the slow held-back lot to get the burn rate close to nominal, and vice-versa. So when you buy canister grade powder, unless the new lot came out of the factory just happening to be already inside the canister burn rate window, then you are buying a blend of new and old powder with no knowledge of the age of the latter. In the case of your '98 and '99 N140, I'm guessing one year the base bulk powder lot was too slow and the other year it was too fast, so one was blended with a held-back fast lot and the other with a held-back slow lot to adjust the burning rate. The held back lot that went into the '99 was getting older than VV realized, and that caused the problem.

The N140 lot problem has been, as you noted, pretty widely reported. Dumping it avoids the bore rust I experienced. My gun looked clean when I put it away for a couple of months, but when I next got it out the bore was lined with fine surface rust. No powder frugality is worth that.

As to Buck's idea to adding new stabilizer to old powder, that is what the Olin spherical powder process was invented for. New stabilizer cannot simply be applied to the surface, as some deterrent coatings can. It has to be an intimate mixture throughout the substance of the powder. This means the grains have to be redissolved in solvent, the deterioration products washed out and neutralized with a carbonate until the pH is correct, and then new stabilizer added and new grains formed. During WWII there were aging stockpiles of artillery powder in linen canisters and other powders that were reaching stockpile their age limits. The Olin process was able to salvage the remaining good nitrocellulose in the powder for use in fresh powder. (See Hatcher's Notebook, pp 219-229).

Heat and UV light (and higher energy forms of radiation) can cause powder to break down at an accelerated rate. Air, absent unusual humidity levels, will not, as there is a lot of air not only between grains of powder but in all partially filled containers. I have a small remaining quantity of Brigadier 4065 at the bottom of an 8 lb container where it has been since before Scott's rifle powder plant burned down over 20 years ago. It is still just fine and occasionally sampled for ballistic comparison, as it was a great .30-06 powder.

On the other extreme, I recently opened a new, sealed, 1 lb container of the discontinued Accurate 3100 powder of about the same age as the 4065 and that had been kept in the same cool, dry basement. It smelled strongly of darkroom-like chemicals. No red dust or visible red gas fumes yet, but I immediately took it out to the garage before the fumes could find their way into another powder's container. Now that I've opened it, I can smell the odor even around the tightly closed lid. It will fertilize the lawn. No visible lot number, but its a modern brown HDPE container with red cap, and anyone else who might still have some of this old powder around should check it.

Making up test loads with good smelling, red dust and fume-free old powders is no issue, as they go bad over a period of months and not minutes. Just don't load old powder too far in advance of making a ballistic test.

On reflection, I think the main hazard in mixing old powder with new is the habit of doing it. Suppose you buy some canister grade single-base powder that was burn rate adjusted with a 20 year-old lot of held-back powder. You keep it 7-8 years so it is now has some 27 or 28 year old powder in the can. You mix it with your new powder, and then, when that batch is getting low, you mix it with the next canister you buy 7 or 8 years later, and so on. If you have a 30 year reloading life and keep that practice, it becomes possible to have some grains of nearly 60 year-old powder in your container.

When I went to shool I majored in chemistry for a couple of years before switching to electrical engineering. We were taught never to return any chemical to its primary stock container once it had been dispensed. Rather, we always had to put any excess in a temporary working stock container that was labeled and dated. The idea was to avoid inadvertent contamination that could spoil the stored stock purity. I think that's a good practice with chemicals in general and gunpowder, specifically. I never return powder from a powder measure to its original container It has been exposed to light and possibly to different humidity, or maybe even a missed grain or two of some older powder has found its way in. I clean and keep and relabel old powder containers as working stock containers for this reason. The 3100 jar will be washed out with an acid-neutralizing cleaning agent like Formula 409 and final rinsed with distilled water, given a blank shipping label and put into working stock service.

 

[buck460XVR]

Now if that were 100% true, then why in the next paragraph are they giving people advice on how to detect gunpowder that has gone bad?

Because in that previous sentence they said, and for the second time I'll quote it......

safe practices require a recognition of the signs of deterioration and its possible effects

.....just sayin'.

Why would they warn about out accumulating old powder stocks? Maybe they belong to the Organization to reduce clutter in the house? Clutter is the bane of society, a terrible illness that well all must try to eliminate. Or maybe they know the stuff will auto combust at some point?

These are pictures of WW2 era powder hoards. The owners of this stuff are likely to die in flames when these kegs burn the house around them.

Because of situations shown in the pics you posted. That is not modern powder nor is is being properly stored. No where did I tell folks to indiscriminately mix new powder with powder 80 years old. Actually I didn't tell anyone to mix powders, only that I would have no qualms mixing 7 year old powder showing no signs of deterioration, with fresh powder of the same kind. I also doubt very much if the owners of those powders are going to die surrounded by flames created by those old powders. Quite dramatical, aren't we?

Ever since I learned about powder going bad I regularly sniff my gunpowder. I break the seal and check. Just last week, when I was reloading for my 35 Whelen, I sniffed this powder and it was bitter. I went around the house smelling chemicals to find something with a similar smell. The base smell was like ammonia. However , it was more bitter than ammonia, more like red pepper in the nose. I poured this 1999 powder out. It was not fuming red nitric acid gas, but, I know from previous experience, old gunpowder will ruin cases in months.

...and that is just just an example of safe reloading. But is it any safer to load powder showing no signs of deterioration and not shooting the cartridges for 5-6 years, than it is to mix a little bit of that powder with a large amount of fresh and not shoot the cartridges for 5-6 years? Or is it the latter safer because you have slowed down the deterioration of the little bit of powder with the influx of new stabilizers or diluted it to the point that it is non-existent? Or is the risk the same?

I believe much of the irrationality about shelf life on gunpowders comes from those who believe I am immortal and so is all of my stuff! . Well sorry, you and your gunpowder have a "best buy" date. And, at some unknown point in the future, you and your gunpowder stash will be dust. While that point is currently unknown, it is fixed, and you will get there.

Since I don't agree with you I must believe I'm immortal? SMH. No, I just evaluate risks and then proceed with caution applicable to that risk. I could claim any powder over 7-8 years old is bad and folks need to throw it away or shoot it up immediately. But since the powder companies don't tell us that, I don't either. Powder companies also do not make the big deal out of deterioration of modern powders like some here. I wonder why that is. Do they want us to blow ourselves up?

Given that the lifetime of gunpowder is unpredictable, I consider it best practice not to mix different lots, especially lots that are years or decades old. In fact, based on all the powder I have had to toss because it went bad, I am going to say, shoot up your oldest powder, make a point of using it up in ten years, don't expect anything to last 20 years. But if you have 20 + year old gunpowder, shoot it up.

Given that the life of gunpowder is unpredictable, I consider it best to know how to identify powder that has deteriorated. I too suggest shooting your oldest powders first if they shoot well for you. If powders do not perform well, one should dispose of them properly. Powder is relatively cheap. If it is not worth loading behind a projectile for you, or you suspect any kind of deterioration, I would suggest to dispose of it properly. I would not mix WWII era powder of the same kind with any of today's powders, not just because of the risk of deterioration, but because many formulas have changed over 80 years. I also would suggest not to invest in powder that one is not going to use within a decade, for all of the above reasons. I have no powders in my reloading room that are more than 5 years old because I rotate my stock. This is why I have no qualms about mixing old with new. 2 more years would not make a difference to me. 80 would. Again, others are free to do what they want and I won't chastise them. I ask others do the same.

 

[Slamfire]

Given that the life of gunpowder is unpredictable, I consider it best to know how to identify powder that has deteriorated. I too suggest shooting your oldest powders first if they shoot well for you. If powders do not perform well, one should dispose of them properly. Powder is relatively cheap. If it is not worth loading behind a projectile for you, or you suspect any kind of deterioration, I would suggest to dispose of it properly. I would not mix WWII era powder of the same kind with any of today's powders, not just because of the risk of deterioration, but because many formulas have changed over 80 years. I also would suggest not to invest in powder that one is not going to use within a decade, for all of the above reasons. I have no powders in my reloading room that are more than 5 years old because I rotate my stock. This is why I have no qualms about mixing old with new. 2 more years would not make a difference to me. 80 would. Again, others are free to do what they want and I won't chastise them. I ask others do the same.

I don't think we are in any major disagreement. It is all a matter of self imposed limits and judgements. We basically agree that old gunpowder ought not be mixed with new, it is a matter of what constitues old. I will say, based on what I have experienced with Vihtavuori powder, that powder deteriorates faster than any IMR or Hodgdon powder I owned. And I have been tossing Accurate Arms powders from the nineties so I am not very positive about their long term storage or in mixing them, even of the same vintage.

I also doubt very much if the owners of those powders are going to die surrounded by flames created by those old powders. Quite dramatical, aren't we?

Hey houses do burn down. There is no national register, no News Media collecting accident data. But there are accounts of fires. Where there is smoke there is flame!


Military Surplus Powder autocombusting

http://www.ar15.com/archive/topic.html?b=6&f=3&t=248538

I run a long range shooting club here in NM. Yesterday a member approached me with a question about a powder he is using. He said " it's fuming" ........What?
I walked down and sure enough the powder was outgassing a very heavy oder of ammonia and Nitric Acid fumes. The powder was slowly turning sticky and had,from over night, corroded the brass cases and the projectiles.
This powder is milsurp pull down IMR-5010 powder that was sold in bulk from the long gone Talon company. Weidners and Pats reloading sells this powder in black plastic 8 pound jugs. There are no lot numbers or dates on the label.
I have been reloading since 1964 and have never seen this happen before. As you know nitro-cellulose uses Nitric Acid to make the propellant. Some how the acid was not neutralized correctly. When the acid is not removed from the powder grains, the deterent coating will break down and uncontrolled burning will happen. The powder may detonate rather than burn

If any of you have any powder that was OK a few months ago you may want to check it again. This powder was normal just last winter. Now it is breaking down. It was stored in a cool room. It was not left in the sunlight.

Chris at Weiders has been notified.

This was purely a PULLDOWN powder issue. NOT a Virgin IMR-5010 issue. I know the guy this allegedly happened to (Paul A. of Albuquerque). I suggested he post the source, acquisition date, etc but to date he has not. He told me the powder was PULLDOWN IMR-5010 from www.wideners.com. Wideners allegedly told him they would not replace the powder as his storage of it was beyond their control. Also, he had no direct status with them as he obtained this particular jug from another guy that had bought it from wideners.

I personally know the guy this happened to and unless you see some sort of acrid fumes coming off your powder, I wouldn't worry about it. Paul is a real cheap skate. He was loading $2.00 Lehigh 800 grainers with surplus powder. Silly way to save $0.25.
http://forums.gunboards.com/showthread.php?52892-Warning-surplus-IMR-5010-powder-users

1. 10-02-2009, 11:02 AM#6
Cincinnati Kid
Platinum Bullet Member
Join Date
Dec 1969
Location
Cincinnati, Ohio
Posts
421

That IMR 5010 powder that came from Talon has caused several large fires here in Ohio, two of them locally to a friend of mine, and one large fire in Northern Ohio that I know of. Anyone who has any of that 5010 powder that came from Talon needs to dispose of it if it shows any signs of breaking down. I wouldn't trust any of it.

Old Powder Caused Fire!
http://www.thehighroad.org/showthread.php?t=788841
________________________________________

First, sorry for the long post. Second, if I didn't know the people this happened to I would have a hard time believing this, I'd probably call this BS. I hunt at a property owned by someone I used to work with. All I have is his email address. I have been trying to contact him for several weeks via email. He lives over an hour a way and I hadn't tried to catch him at home yet. I finally got hold of him the other day. He apologized for not getting back to me sooner, but he had a house fire and had been dealing with that since the beginning of the month.

I drove there today. There was a trailer set up for his family to live in while the house gets restored. His wife was there when I got there. I asked her what happened. I couldn't believe her answer. Apparently my friends brother gave him about 15 pounds of gun powder for reloading about 10-15 years ago. It never got used. Sorry, I don't know what kind of powder it was. Their daughter just got out of the shower in the room next to where this powder was stored. She heard a WOOOOSH sound and came out of the bathroom to find the place in flames. It started where the old powder was stored.

Luckily, they were able to keep the fire down for a few minutes with an extinguisher and the fire dept responded in about 5, but there was some serious damage. I saw the spot where the powder was kept and the floor all around it charred, the rest of the place sustained heat and smoke damage. They were lucky they were home and someone got on this almost immediately or the place would have been a total loss. The BIL had some more of this powder at his home, he dumped it outside and lit it off. I'm sure he didn't know it would have made good fertilizer.

There was no other suspected cause of this fire than spontaneous combustion of this old gun powder. Has anyone heard of old un-stable gun powder just going up like this? I've got probably 20 pounds of powder in the next room and I'm sure many of you have more than that. After hearing this, I'm going to make sure it all gets used or at least smelled now and again if it sits for a few years. Green grass beats a burned home!

This section is from the Dec 2003 Propellant Management Guide:

. During the period 1984 through 1997, seven propellant auto ignition events occurred at U. S. Army Material Command (AMC) Installations.

1. 1984: Lake City AAP

IMR powder that was only 5 years old auto ignited and the above round magazine and its contents were destroyed. More than 100,000 lbs of powder deflagrated.

2. 1984: Lake City AAP

The same lot of IMR powder, a fragment quantity isolated and saved for critical production testing, auto ignited two months after the previous fire. Only a small quantity of powder was lost, but another magazine was destroyed.

3. 1985: Blue Grass Army Depot

The local-stocks storage magazine use for demilitarization activities contained high explosives material as well as unmonitored M10 propellant powder. Auto ignition of the powder and its resulting deflagration gradually ignited the other energetic materials present. The earth covered magazine and its contents were destroyed.

4. 1987: Lone Star AAP

Benite was stored in a heated magazine so that it could be temperature conditioned prior to loading into production items. The building became overheated which accelerated the rate of decomposition of the benite to a point that auto ignition occurred. The structure and contents were lost.

5. 1989: Hawthorne Army Depot

8-inch, 55-caliber propelling charges loaded with single-base propellant auto ignited in an earth-covered magazine more than one year after the Navy ordered the lot destroyed due to low stability. The magazine contents of 30,715 lbs of various propellant were destroyed and the magazine was heavily damaged.

6: 1996: Red River Army Depot

Explosion charge assemblies for large caliber artillery rounds, each charge filled with only one ounce of M10 propellant and stored 250 to a box, auto ignited. The earth covered magazine and its contents were totally destroyed.

7. 1997: Hawthorne Army Depot

M9 flake propellant bags that had been removed from 81 mm mortar round were bulk-packed and placed into long-term storage. A container of unstable propellant auto ignited, and all 20,000 lbs of propellant inside the earth covered magazine were destroyed. The magazine was severely damaged. Value of content lost was more than $3,000,000, which the cost to repair the magazine was $164,000.

 

[buck460XVR]

I don't think we are in any major disagreement. It is all a matter of self imposed limits and judgements. We basically agree that old gunpowder ought not be mixed with new, it is a matter of what constitues old.

On this I totally agree. Would I mix 20 year old powder with new. Nope, cause I don't have any 20 year old powder. I only buy powder I know I can use within a few years. Even with the shortages of a few years back I didn't run out, before powder was readily available again. Powder regardless of price is not a value, if and when it goes bad and needs to thrown out. Again, if I was afraid the powder was too old to mix, it would be fertilizer, not loaded ammo.

While I know I'm not immortal, I also know I didn't get old by being stupid, nor was it just dumb luck. I take reloading very seriously and try to use sound judgement, safe practices and reliable techniques when doing so. While my ways may not mirror others, they have worked well for me and proven safe and effective. Still folks need to use sound judgement to determine how they do things, and not just do what I do.

 

[Unclenick]

I would emphasize the checking of powder at each reloading cycle is important because, when you buy a canister grade powder, you don't know if you have any 20 year-old powder in the container or not. It depends on what it was blended with for burn rate control.

I read that Hodgdon improved their QC system in the early 2000's because of problems with significant burn rate variations in some Varget lots that had occurred in the 90's. I don't know if the QC changes did anything about aging, but given the IMR4007SSC recall notice is from 2015, I am guessing that, as distributors, they don't control it that far up the line.

The other thing that can go wrong with powder is someone letting it sit in a shipping container for too long. Appliances are usually rated to withstand 170°F for two weeks in their shipping boxes due to how hot those containers can become in some locations. The Navy and Norma tests done at around 140°F break down new powder in under two years. Getting it even hotter would rob powder of life expectancy fast.

As you know nitro-cellulose uses Nitric Acid to make the propellant. Some how the acid was not neutralized correctly.

I'll just mention, for anyone following the chemistry, that the above is incorrect. Nitric acid is used to nitrate cellulose into nitrocellulose, and any acid that may have been left improperly neutralized or washed out would then be scavenged by the stabilizer added during processing the nitrocellulose into gunpowder. Mind you, that would reduce how much stabilizer was left, and therefore the life of the powder lot, but the acid would be gone. Any nitric acid from breakdown would be newly formed from hydrogen and nitrate ions that came from deteriorated nitrocellulose molecules.

In practice, hydrogen grabs oxygen to make water, first and foremost, which dissolves other gases, including hydrogen and nitrate radicals normally in aqueous nitric acid solutions. But stealing oxygen from nitrate radicals leaves some nitrogen dioxide behind. That's the red gas. It also dissolves in the water formed and in any water present due to humidity until the water is saturated, at which point it fumes off.

 

[Metal god]

you don't know if you have any 20 year-old powder in the container or not. It depends on what it was blended with for burn rate control.

I know they blend powders but do you really think they blend 20 year old powder to new powder ? That just does not sound reasonable to me . In some cases powders only have a 20 year shelf life so blending a 20 year old powder to new just seems stupid on the manufacturers part . Even if adding it to powder that is expected to last 40 years is still cutting it's expected life in half . As a company making this type of product , purposefully severely reducing it's shelf life would not seem like a good business practice .

What cool dry place would they be storing this rather large amount of powder for 20yrs . Seeing how it's been 20yrs I'd assume they have even more 18 , 16, 14 , 10 year powders they are storing as well . Oh then there's ALL the different powders to consider they must be storing for many years , remember we're not just talking H4895 here . I'd assume there QC would be good enough to be able to mix those powders well before the 20 year mark to get the burn rate they are looking for .

This is not to dispute the over all point being made but 15 to 20 year old powders being mixed with new powders to be sold as NIB powders does not sound like a good idea .

EDIT

I'd think they could just purposefully make a powder a tad faster in order to mix the slower lot that's been around a year or two with it . Then use that mixed powder as bulk grade powder rather then letting any powder sit around for many years .

 

[Unclenick]

MG,

If they could make a faster or slower lot reliably on demand, then they would just make the bulk burn rate correct in the first place. A big part of the problem is the purity levels of the constituent chemicals would have to be higher to do that, and that can increase material cost ten or twenty fold pretty easily. I ran into this working with pentadecane as a phase change material for cold packs for vaccine transport twenty years ago. The technical grade stuff had almost twice the heat capacity and a much tighter melting range than the solvent grade, but it was $60.00/lb verses $2.50/lb, so guess what the plant needed to use?

One results of cost and some process limitations is powders come out of the plant with a span of lot burn rates. The probability that any lot will have a particular burn rate will describe a bell curve with the target burn rate at the center peak. An attempt to intentionally make a faster or slower lot will move the bell curve center up or down the burn rate scale, but you'll still have a lot of overlap of the new and original curves. A lot you run with the new target rate using the usual materials and processes may turn out well inside the usual burn rate range in the end. You might have to make a number of lots that way to get what you want, and that would make the investment unattractive.

I would need to pick the brains of someone currently in the industry to know, but based on the probability issue it seems likely that if you got an unusually fast or a slow lot making the powder the usual way, since you still have all the same costs of production for a lot that hit the target burn rate perfectly, you wouldn't want to lose that by just dumping it on the surplus market or absorbing the cost of reprocessing it. You could sell it to an ammunition maker as a special lot suitable for cartridges the powder type isn't normally used in, or you could set it aside to be used for blending at some uncertain pace in the future.

I was in a lab last year which had state-of-the-art bench top rapid NMR Spectroscopy gear that gave a complete organic chemical profile of a food sample in about half an hour. Astonishing compared to when I was in school. If I were running a powder plant, I would run analysis on samples of a fast or slow retained lot to determine the remaining stabilizer content and judge from that whether to blend it with a new powder or not, and not use age at all. Age is, in this discussion, just a surrogate for stabilizer loss, and given the various recalls and my own experiences with powders that went bad in under 20 years, it doesn't seem to be an entirely reliable one.

I'm sure no maker sells poor powder on purpose or stores it badly on purpose or gets bad raw chemical impurities on purpose. I'm sure, for reputation purposes, they would have every lot hit the target burn rate right out of the drier and then last indefinitely if they could. But the nature of the process and cost constraints won't allow that. The probability of breakdown initiating after a certain period will have its own bell curve.

 

[hdwhit]

FLChinook wrote:
I've always felt that powders, properly stored, do not age. What say 'ye??

As to this statement, what Unclenick said about your feelings in post #4 is 100% correct. The manufacturers formulate their powders for long shelf life and add antioxidants and other stabilizers to help achieve that, but in spite of this, powders do deteriorate over time.

Also, it is very poor practice to get in the habit of mixing powders. The "only one powder container on the bench at a time" rule was formulated for a reason. When someone thinks they are returning Powder "X" to its container, but inadvertently dumps it into a canister of Powder "Y" is how catastrophic accidents happen.

Your original post said the existing canister is as much as 8 years old. Are you going to be using the new canisters at the same rate? If your pace of consumption isn't about to accelerate tremendously, by the time you use up your new canisters, some of the powder in them will be sixteen years old. And yes, the new canister has new stabilizers and anti-oxidants, but you can't assume they will "migrate" to the old powder you just added.

Have I always followed that rule myself? No.

Have I taken the remnants of a nearly empty can and added it to a new can? Yes.

Have I just been lucky so far? Most Certainly.

We ignore best practices at our own risk. We may ignore then and get lucky, but failure to have a catastrophe doesn't mean that what we did was wise or prudent.

 

[Metal god]

Thanks Unclenick , I did not consider they can and would run tests on the stabilizers in the powder to determine if mixing it would be a good idea . This brings up the next logical question . How deteriorated would they let the powder get and still allow mixing ? I'd have to assume not much more then ( using the year analogy ) 5 years of deterioration would be max I'd think or 25% ????

Also , not sure if this was discussed but Assuming the powder is stored relatively consistently does powder generally deteriorate evenly or does it slowly deteriorate then one year it just starts falling off the cliff sort of speak ?

 

[Unclenick]

MG,

If they are doing a I suggested (and I haven't talked to any of them about it), I'm thinking they probably would project the expiration based on the lot's measured stabilizer deterioration rate history. With different balances of chemical species and each chemical having different lot impurities, they probably break down at different rates that you can attempt to project by trend line.

Your second question is a key one. The bigger the powder mass, the greater the chance that not just the odd individual molecule, but several near one another somewhere in the mass will break down at the same time, creating a pocket without enough stabilizer to scavenge all the acid products, so the breakdown spreads out, staying ahead of the neutralizing activity. This starts the mass breakdown. It's why you can load a bunch of rounds and only find breakdown in a few, as I described before. The more stabilizer that is depleted, the greater the odds of this happening become.

 

[stevelyn]

I've done it, but be aware if you do, this can happen.

http://www.ramshot.com/consumer-alert/recall-notice/

 

[Unclenick]

I don't see a reason given for that recall. I wish they'd state the problem. My memory says that at one point there was a recall of powder because a similar looking but wrong type was in some packaging. I don't even recall what company it was at this point. Over time, things happen.

 

[Slamfire]

I'm sure no maker sells poor powder on purpose or stores it badly on purpose or gets bad raw chemical impurities on purpose.

While Corporations make five year plans, everyone knows they are fiction, the only plans that count are this year’s, and maybe next year’s. Corporations are in it for the short term, are in it to maximize profits now, not tomorrow, not next week, but now.

If a Corporation is given a choice of scrapping defective product and thereby losing profit, or selling it, to a buyer who does not know it is bad and can’t prove it is bad, what course of action do you think the Corporation will take? The answer is that the Corporation will ship the defective product and take the profit.

Anyone remember the Volkswagen engineers, guys who were so environmentally righteous they grew wings? Do you think Volkswagen Management and all the Software, and Test Engineers did not know what they were doing when they wrote the software requirements, verified the software, verified the emissions system which only turned on when the car was in an emissions test?

The future is hard to predict, but in the short run, Volkswagen made one heck of a lot of profits selling zippy, fuel efficient, highly polluting diesel cars.

I am 100% certain that if defective powder lots made it on the market, it was because Corporate Management over ruled their written Quality Assurance requirements and shipped bad product, because, the company would make profit now, and the problems of sub standard gunpowder would not be revealed for years to come. By then it would be someone else’s problem. I am equally certain they did not start out meaning to make bad product, but given that defective product is what they produced, that is what they shipped. And that is what you bought.