Old Dupont IMR powder data?

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Foton

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Greetings;

A friend who has been reloading for many years recently gave me a good deal of vintage powder (@30lbs) - rectangular metal 1lb cans, unopened. I queried Hodgdon today and was told that the powder was in all likelihood good to use (when I do open it examine physically and of course be on the look out for acidic smells etc.). They did caution me though that the formulation and hence pressure information *may* have changed from when DuPont manufactured the stuff I have (@30yrs ago) and so should not rely on current load books.

So my question to the group is does anyone have any data for: IMR4831, IMR 3031 and IMR4064 manufactured by DuPont @30+ years ago that they might be willing to share?

I expect to load the powder for a M38 6.5x55Swede, 140gr projectile but any data for 30-06, .308 etc would be appreciated.

Thanks,
 
Foton,

If you use starting loads or reduce max loads by 10% for the same make of powder in current reloading manuals, you will not get into any trouble.

Don
 
Amazon has the 'DuPont Handloader's Guide for Smokeless Powder 1975-76'
and the 'Hornady Handbook Volume 2'
for sale used.
 
Older manuals

Thanks for the tip on used book stores. Our local library didnt have anything sufficiently aged but Amazon did and have ordered some. Eventually they'll get here.

In the meanwhile let me thank everyone who answered and helped me out.

Happy Shooting!
 
I am of the opinion that IMR powder didn't, or hasn't changed over the years.

The pressure testing methods & load manuals sure have though!!

I'd feel safer using old powder with new IMR data then old powder with old IMR data.

rc
 
I am of the opinion that IMR powder didn't, or hasn't changed over the years.

The pressure testing methods & load manuals sure have though!!

I'd feel safer using old powder with new IMR data then old powder with old IMR data.

rc
My thoughts exactly.
 
First, I'll say what you were told is lawyer boiler plate. It's all 'cannister' powder and the burn rates have been carefully maintained in every lot ever made. Not only is there no reason for makers to 'change' a standard powder it would be law-suit stupid to do so - and they are NOT stupid people. If the makers want to market a different burn rate they simply give it a new name and sell it under the new name, they don't just dump something different into cans and paste old stickers on it.

Second, all loading data is generic by powder type and bullet weight. All manuals tell us to 'start low and slowly work towards book max unless you see excessive pressure signs earlier." Do that and it won't make any (hazardous) difference no matter when the powder was made or what bullet or primer or case you use; ignore that rule and no loading data can save your fingers. I still happily use my original Lyman #43, it was the only manual I had for my first five years of reloading and felt quite safe because I followed that one "max" load rule that covers all variables!
 
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Don't think IMR data has changed at least since the 1980's when I started using it. I agree that you should consult several data sources and start low and work up. The IMR Reloaders Handbook is a good source for IMR data but read where it says start 10% lower and work up. The IMR Reloaders Guide has data for rifle, pistol, and shotgun.
http://www.imrpowder.com/pdf/IMR_rifle.pdf
 
Old IMR

I started reloading in 1998 with equipment, powder, and components given to me by a friend. The powder at the time was 20 year old IMR 4064, H4831, and Bullseye which had been exposed to heat, cold, and containers had even been wet and dryed several times before I received them. After checking the condition of the powders and finding them good I proceeded loading with current (1998) manuals and never had a problem. I have since been given other old powders and most have been fine. Only three-one pound cans have been found to be going bad and were disposed of. Two had rusty red flakes intermingled with the powder and one had a very acrid smell to it.
 
I have some old books for reloading that are from the 40's-50"s and the loads are not that much different in books today (slightly lower) than then on propellants that are still made. As stated if you reduce the MAX by 10% using new data to start and watch for trouble there should be no problems with your loads. I use the older books for some of the old shotshell loads especially or for that odd can of old propellant I might find at a great deal.
 
I agree with rcmodel. I wouldn't have a problem with using the old IMR powder with loading data from the current manuals. I started loading military surplus 4831 powder from large rectangular containers back in the 1960's and when commercial IMR 4831 came out I thought they were the same. The first rounds I loaded showed excessive pressure on the primers and I quickly lowered the charges. To summarize, military surplus 4831, IMR 4831 and H 4831 are all different powders and full power loads must be approached with that in mind.
 
I started loading military surplus 4831 powder from large rectangular containers back in the 1960's and when commercial IMR 4831 came out I thought they were the same. The first rounds I loaded showed excessive pressure
You too!

I locked up the bolt on my old 03A3 Springfield long about 1965 with the same load of IMR-4831 I had used for three years with H-4831.
Had to beat it open with a wooden mallet!

rc
 
We know that now.

But in 1962-65 when I was 18-21 years old, and had to wait on the pony express rider to bring the American Rifleman to Kansas.

And we were too busy chasing girls, riding motorcycles, getting drafted, shooting coyotes, farming, and trying to learn how to reload all at the same time?

Who had time to read the Hodgdon vis IMR powder warnings when the mail finally got here?? :D

rc
 
Yeah, rcmodel, in these days of "instant knowledge and gratification" via the internet, a lot of the younger guys don't realize that we got our monthly "fix" of knowledge thru magazines such as Shooting Times, Guns & Ammo, and the American Rifleman. I've still got a letter somewhere that Elmer Keith sent me telling me his favorite loads for the .30-06 and .357 Magnum.

Don

P.S. - Elmer was a terrible typist.:D
 
Yeah, rcmodel, in these days of "instant knowledge and gratification" via the internet, a lot of the younger guys don't realize that we got our monthly "fix" of knowledge thru magazines such as Shooting Times, Guns & Ammo, and the American Rifleman. I've still got a letter somewhere that Elmer Keith sent me telling me his favorite loads for the .30-06 and .357 Magnum.

Don

P.S. - Elmer was a terrible typist.:D
Elmer's taxidermist told me he was a terrible liar too. ;)
 
Older data

Wow, thanks again everyone particularly to the folks who took the time to scan data sheets.

I've checked all the powder and only found 3 1lb cans that were suspicious - really only 2 of the powders had gone off, sections of the lid of the other can crumbled into the powder as I prised it off so elected to dispose of it. Anyhow have loaded up several (starting low) strings of 6.5 Swede to try in my M38 (in this case using the 4064) as well as some modern RL22, both using 140g Sierra MK HPBT as controls. Will proceed at 2grain intervals and see how they distribute.
 
"Will proceed at 2grain intervals and see how they distribute."

"Intervals" of 2 grains is NOT a small increment.
 
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