Blending powder for better consistancy... no not different powders...

[Magnum Wheel Man]

I'm curious of your guys thoughts as to blending new & older powders as you work through them to insure better consistancy ???

I have several pounds of powders that are 12-15 years old... I've also just reciently bought new replacements... as I'm developing some accuracy loads... I've thought about blending the older with the new... & thinking about doing it in the future as the powders are fresher...

your guys thoughts...

[Gewehr98]

Mixing a 12 year old can of, say, Bullseye with a new one could offer a surprise or two.

The mixed powder might be in the same ballpark as either parent, but I'd definitely start on the low end of the reloading data.

Why not just shoot the older stuff first, saving the newer stuff?

[Nnobby45]

I regularly blend different lots of powder when a can starts to get low, but I don't like the idea of mixing new with real old.

Where was the powder stored. In the garage where it's hot in summer and cold in winter? Indoors at constant temperature?

You might get away with the latter without noticing a difference, but I would keep the old stuff together and use it up. If it's bad, or about to go bad, you don't want to contaminate your whole supply.

[Unclenick]

Its one of those things that is probably OK 99% of the time, since canister powder makers hold back extra fast and extra slow lots specifically for the purpose of blending with newer lots to adjust the burning rate anyway. However, if the storage conditions have been off or the old powder is starting to deteriorate, you could conceivably have issues with sensitivity that might be unhealthy. It becomes a judgment call based on your ability to evaluate the condition of the old powder and tell whether it is breaking down or not? Acrid smell, reddish dust forming on the surface, changes in load performance. If you're not confident you can do that or are not confident that the storage conditions are good, don't blend.

[Ruger4570]

Whenever I buy new powder I add what is left of the old powder and mix well. I mix of course the same powders, not something like Bullseye with IMR 3031.
Speaking of bulls eye and powder storage.
I acquired an "opened" can of bullseye back in the 1960's. I don't know how old it was when I got it or how long it had been opened. I really never had a need for Bullseye as I preferred powders that wouldn't allow a double charge with noticing it. I stored it in NY in my basement, not necessarily super dry but cool. I later moved to Tucson, Arizona and the powder was stored in my garage which often in the summer would hit 120 degrees or more.
I finally had to move back to NY and stored the powder in an unheated storage facility for a couple of years.
Last year, mostly because I got tired of moving this can of powder I decided to burn it up in some shotshells.
From what I can see it performed perfectly regardless of 45 years of really bad treatment.
I think powder degredation claims are way too suspect as far as accuracy and fact. In the 50 odd years I have loaded I have YET to ever see a powder go bad. Not single base or double base powder.
I am not limiting my experience to the Bullseye, it is just the one I remember in particular. I have had MANY powders with similar not great treatment perform perfectly.
My "personal" opinion is that it is mostly wives tales carried over from powders no longer made and that were made around the turn of the century.
I know a whole bunch of reloaders and to date, not a single one I have spoken to has ever had a powder go bad, smell funny or not perform.
I think the whole subject is WAY overblown as are most "wives tales"

[Magnum Wheel Man]

all the "older" powders were stored as good as could be... I was just wondering since I have some loads that I'm wanting "benchrest" type accuracy out of, & I'm currently starting with these older powders, ( which are performing fine ) if it wouldn't be better to blend each last 1/2 pound or so into the new canisters... I'd think it would give me a smoother transition from lot to lot even on "fresher" powders ???

[Sevens]

Here's how it looks to me:

If you have, say, 5 pounds of powder from years gone by... and you have 5 pounds of new powder from today, and you are moving yourself to a deserted island never to return, then BLEND 'em.

Or, if you intend to use that 10 pounds of powder in one particular caliber and you know it will last you for the next 40 years, then blend 'em.

But if you ever plan on buying more powder, you shouldn't blend them. Simply because your "old 5 new 5" blend is one that you won't ever be able to duplicate again.

Much like your "old 5" which you can't duplicate, why use 5 new pounds to make a 10-pound can of powder that has a blend that can't be duplicated?

[darkgael]

About consistency. Will doing what has been proposed actually yield a more consistent propellant? Will you end up with a third powder that yields different results than the other two. Do the old and new powders on hand yield different results?
From what I can see, referring only to Bullseye in my .45, the answer to the last question is No. It may, however, depend on what one considers "old".
until last January, I had been using Bullseye, for match loads, that I had bought in 2007. I finished that lot and opened a can that had been bought in 1989. The gun shoots to the same place in the same way with the "old" as it did with the new.
Pete

[Magnum Wheel Man]

I'd like to get to where I'm buying 8 lb drums, but until I develope a good load, I don't want to buy that much bulk of every powder I've got ( I think I have nearly 20 different powders on hand ) some a Dupont or discontinued brands of numbers I'll probably sell off some of them at the next gun show, but I'm not seeing alot of difference between my oldest Hercules Unique & my newest can of Alliant Unique... or my 15-17 year old canister of H-110 & my newest ( just purchased last month )

I guess I have so many powders, because both mine & my father in laws stuff was combined after he died 12-14 years ago... then I went through almost 10 years that I didn't reload... so now that I'm back into it, I'm trying to sort through it all

BTW... do you guys date your powders as you buy them ??? I started doing that, when I combined both our collections of relading stuff, so I have alot that aren't dated, but since this is a hobby I don't plan on giving up any time soon, I thought it was a good idea...

[jmorris]

your guys thoughts...

My first thought was "crack doesn't smoke itself".

If you are looking for consistency, why would you take 1 pound of thousands of particles of powder that were made at the same time and place then mix in a totally different batch of stuff and expect it to get better?

You wouldn’t even be able to tell if you have them “blended” or not either so you would likely have a round with 100% powder from lot “a” and another from 100% “b” then one from a 50% mix of both, then a 20%/80% mix….

[Magnum Wheel Man]

You wouldn’t even be able to tell if you have them “blended” or not either so you would likely have a round with 100% powder from lot “a” and another from 100% “b” then one from a 50% mix of both, then a 20%/80% mix….

hmmm... I'm in the powder blending business albeit not gun powder, but it's not rocket science to get 2 powders of similar bulk density & granulation properties to blend well...

[D. Manley]

I regularly blend different lots of powder when a can starts to get low, but I don't like the idea of mixing new with real old.

+1. I make it a practice to start a load run with a full PM cannister so when my powder jug no longer has enough to fill it, I combine with a new one. I don't think I'd want to mix anything really old with frest stuff, though.

[Gewehr98]

hmmm... I'm in the powder blending business albeit not gun powder, but it's not rocket science to get 2 powders of similar bulk density & granulation properties to blend well

You're only working with two attributes, and that's just a portion of what makes smokeless propellant act a certain way.

You're creating a 3rd, unknown hybrid powder, with qualities that still won't be repeatable several pounds down the road as formulations change from the factory.

I wouldn't do it. I'd just use up the old stuff, and move on to the new.

[wncchester]

"why would you take 1 pound of thousands of particles of powder that were made at the same time and place then mix in a totally different batch of stuff and expect it to get better?"

The point isn't to make it "better", it's to equalize any small differneces that may - usually are - present. And it's a good idea. I have long mixed different lots to accomplish exactly that.

Don't over study the issue, it's really not that big a thing. Contrarary to "web knowledge", the burn rates and stability of different lots of cannister powders, including those of different ages, are quite small so mixing them isn't making a "new" powder. It only means we have to tweak our loads once, if at all, if we mix several cans rather than repeating it with each new container.

If they are stored reasonably well, both powder and primers are FAR MORE stable than many "new guys" today seem to think. I've successfully used lots of 50 year old stuff of both so I know what I'm talking about.

[James R. Burke]

I will only mix if I bought them very close together. I put the one running out on top of the one being opened so when its used the one left over will come out first. If there is a period of time from when I bought them I will use the old one first, and not mix them. Things can change.

[crowbeaner]

I don't blend powder of any make or type simply because of the variations between lots and cans- see Alliant Blue Dot warnings. Also, the data for H380 in the newest Hodgdon booklet lists several charges that are 4 to 5 grains higher than the charges I've been shooting for decades. That in itself tells me that the powder is different or the techs that do the testing are smoking 5 leaf tobacco at lunch. NOOOOO! Bad JUJU! CB.

[Slamfire]

Half of all the surplus IMR 4895 I purchased went bad.

The first 16 lbs, I used up eight pounds quickly. For whatever reason, I pulled the bullets on some of that stuff and found green corrosion on the bases of the bullets.

The last eight pounds, it sat around. When I opened the bottle top, it smelled bitter. Red dust flew around.

I gave it to a machine gunner guy. He put it in the laundry room. The bottle got a piece of laundry over it and over night acid gas from the bottle ate holes in the laundry. The guy then poured the stuff out over the lawn.

Since then I have had surplus 4895 powder go bad in the case. Green corrosion on the bottom of the bullets and cracked case necks.

This year I was able to talk to a Navy Energics specialist. He explained that powder deteriorates from the day it leaves the factory. The Nitrocellulose and nitro glycerin want to combine to form a lower energy molecule. Nitric gas is released in the chemical reaction. The rate of combination is directly related to temperature. The higher the temperature the faster the reaction. Powder contains stabilizers. The Navy samples its powders and propellants. If the powder is outgassing nitric gas (as determined by a paper that changes color), the stuff is tested to see how much stabilizer is left. If the amount is less than 15%, the lot is scrapped.

The Army does it different. The Army scraps small arms powders by time. Double based powders and ammunition are scrapped at 20 years, single based 45 years.

The military does not talk about this, but bunkers and ammunition storage areas have gone Kaboom due to old powder. That nitric acid builds up, creates heat, and the stuff blows up. It blows up inside the case or the shell.

http://www.liveleak.com/view?i=13c_1205681217

The expert suggested that it is likely that surplus military powders are not on the market anymore due to liability issues. The stuff was scrapped because the military decided it was not safe to keep around anymore.

If the powder has turned red, or smells like acid, it is way beyond its safe limits.

I talked to Alliant powders. They told me that if the plating inside the old cans is has rust spots, the powder is doing that, and the powder should be dumped.

For this reason, I do not think it is advisable to mix old powders with new. Why have the whole lot go bad?