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CFE-223 may not be age-stable

CFE-223 may not be age-stable powder!
Today, I was updating the GRTools powder model for CFE-223
load data:
175gr RDF
45.2gr CFE-223 @ 2.800"
Federal LR Match, Lapua 308 case
Howa 1500 22" 1:10
Average MV 2709 fps at 68 (Labradar)
Last year in Summer 2021, I had an almost identical load:
175gr RDF
46.3gr CFE-223, @ 2.850"
LR (S&B or CCI not sure), same Lapua 308 cases
Howa 1500 22" 1:10
Average MV 2648 fps at 91F (Labradar)
First, you notice that the aged powder produced more MV with 1.1gr less powder and at lower ambient temperature.
More MV means more Pressure behind the bullet.
Thus, I calibrated the CFE-223 to the new observed values for the load data I loaded for last Sunday. The powder model was named CFE-223-2022
Then, I added a relative bullet jump of 0.050" for last year's powder model to accommodate the different COAL between the two loads, 2.850" (old) vs 2.800" (new)
Then, I calibrated the powder last year observed MV of 2648 fps at 91F and named the powder model CFE-223-2021.
GRTtools revealed:
Summer 2021 CFE-223 Ba is 0.5335
Spring 2022 CFF-223 Ba is 0.5430765
 
I've had some velocity swings in CFE that I think are humidity related. I will be besting it as soon as my 100Y re-opens. It's temporarily shut because of HVAC issues.
 
I have noticed this as well. I thought I was seeing lot to lot variation, along with some temperature variability - I never considered age.

As long as the groups stay tight, I can manage changes in MV and resulting elevation adjustments for my match schedule.
 
My velocity swings weren't from temp, the only variable was humidity. I loaded in a low humidity basement and the range is temp controlled.
 
I use lots of win-748 ball powder and never had any issues besides a bit of temp related velocity swings.

Once I open a bottle of powder I store it with Saran Wrap (4 layers, aka folded twice) under the lid. Weather it helps or not I don't really know, but it makes me feel better !

PowderStorage.jpg
 
I’m adding Integra humidity controllers to all my open jugs of powder. 55% is what the factory uses. Anything above or below will change the burn rate from the testing I’ve read.
 
Funny; I loaded some 6BR loads with CFE223 recently, using GRT as a starting point. I thought the suggested loads were a little off, and went back to a previous load out of caution.

I was thinking a change to the powder profile in GRT?
 
Funny; I loaded some 6BR loads with CFE223 recently, using GRT as a starting point. I thought the suggested loads were a little off, and went back to a previous load out of caution.

I was thinking a change to the powder profile in GRT?
The GRT has auto powder tune, just click on the OBT tool make a new powder model after you enter the measured MV.
 

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