How much do powders change over time?

[sfl_gunner]

I saw a post about finding old loading data and it reminded me of this topic. How much do powders and load data change overtime?
For example in some old manuals IMR 4227 is listed as suitable for .223, .308 Win and .30-06. Yet none of the newer manuals lists these loads.

 

[Charlie98]

How much do powders and load data change overtime?

Those are two very separate things.

Powders change over time (reformulation, source, etc) but generally stay in the same behavior range. Data, on the other hand, can change significantly... largely because of testing methods, and primarily the way pressure is tested and reported (CUP vs PSI.) There are also differences in bullets and other components.

As far as powders coming in or dropping from favor... testing methodology may have something to do with that. Your example of IMR4227... that is a very, very fast rifle powder, and the people working up the new data set may have not included it because there are other powders that work better, now. Another example of that would be WST in the 9mm... you can't find current data for that combination, you have to go back to older data to find it.

 

[Buzznrose]

Higher lawsuit numbers and lower testosterone numbers are in direct correlation to revised load data…..

Of course, that’s just speculation on my part….

 

[Hugger-4641]

I presume by "powder change over time", you are asking if IMR4227 20yrs ago is the same as a brand new batch?
In which case, Charlie98 answered that well.
How much a container of "stored" powder changes over time is another matter. All depends how it was stored.
As for load data, Charlie98 also covered that, but I would add that the test barrel used also matters.
For 9mm, I believe my Lyman 44th used a S&W pistol with a 5" barrel.
I belive the Lyman 50th used something else, but I don't have either in hand at the moment. This is also a factor in different data between current manuals also.

 

[dcloco]

H4895 is a great example.

Find a rectangular cardboard one pounder and it is DEFINITELY different than H4895 sold in the last 25+ years.

 

[Varminterror]

Higher lawsuit numbers

Does anyone have actual reference for the plethora of case numbers in which handloaders have sued reloading manual publishers?

Or an instance of even a single case?

 

[Buzznrose]

Does anyone have actual reference for the plethora of case numbers in which handloaders have sued reloading manual publishers?

Or an instance of even a single case?

Sorry…my weak attempt at humor in our litigation-hungry society.

 

[AJC1]

So the formulations change over time.

The powder uses up its stabilizer and degrades. (Red dust and fumes bad)

Storage and exposure can change moisture content and the more moisture it has the less the power density by weight. This has been tested but no lab grade results as far as I know.

 

[Tall]

I have a can of Dupont 4227 that I still use occasionally. I purchased it in the mid 1980's. It's still good and I attribute that to proper storage in cool temperatures.

4227 data is pretty close to Hercules (Alliant) 2400 data. They are not interchangeable but close.

 

[GeoDudeFlorida]

I think to some extent the variety and options determine what the labs test; and the manuals only publish what a lab has tested. For example, when IMR 4320 and 4198 were plentiful, there was no Varget. It hadn’t been made yet.
These are all .300Savage tables:
1955:
1967:

2003:

2002:

Something to note is that there are various powders which aren’t listed despite being in production the entire time from 1955 to 2003. Also note the differences in bullet technology and how the loading tables reflect those differences.

 

[bluetopper]

Powder companies know there is data out there that is many decades old that people still use. The powder burn rates have not changed.

 

[1-cavediver]

I started using 57 grains of H4831 under 150 grain Nosler Partitions for my .270 over 50 years ago. I still use the same load today with the same outstanding results. FWIW, the newer H4831SC (short cut) performs exactly the same as well.

 

[dcloco]

Powder companies know there is data out there that is many decades old that people still use. The powder burn rates have not changed.

H4895 composition has DEFINITELY changed in the past 30 years. Cannot use new data with the old style powder.

 

[GeoDudeFlorida]

H4895 composition has DEFINITELY changed in the past 30 years. Cannot use new data with the old style powder.

That’s something to keep in mind: Hodgdon does not now and never has made smokeless powder. Ever. The original Hodgdon powders were military surplus sold out of service after the wartime contracts were cancelled and the suppliers were stuck with excess inventory. Bruce Hodgdon bought it by the railcar load and packaged it for public sale. It shouldn’t surprise anyone that the “old H” powders are not identical to the “new H” powders. But they are still very close. I would be interested in seeing the public announcement Hodgdon sent out saying not to use data before XX/XXXX date for H4895. Where is the cutoff?

 

[Soonerpesek]

Sorry…my weak attempt at humor in our litigation-hungry society.

The vast majority of us could sense that when you posted this:

Of course, that’s just speculation on my part….

....................................not everyone is quick round here..........................

 

[sfl_gunner]

Thanks for the responses. I'm more concerned about the data of newer powder (new jugs of IMR4227) and being able to use old data to load certain bullets. I know old powder can be dangerous and unstable.

Side note about old powders. I once got a bunch of reloads along with other reloading equipment. I had no idea who loaded them. So I proceeded to pull all the bullets and dump the powder. Some of the powder was quite deteriorated inside of the cases. Glad I did that instead of shooting random stuff.