has anyone found #9 to be sensitive to compression?
I have been shooting 14 g behind a 165 g bullet and last night loaded 10 165 Federal HST and noticed that two where little long... I pulled and checked powder. It was dead on but the bullets where a few thousandths longer.
This load has never shown pressures, but it has me wondering.
CW
BTW, MAG PRIMER is used.
I don't think you can get enough #9 in a 10mm case, with any bullet, to get you into serious trouble.
I believe it does reach max pressure with heavier bullets, burns too clean not to, but there just isn't room to go over much.
Plenty of load data out there for compressed charges, so I wouldn't be super concerned. I think Wade has reported issues in the past keeping bullets from creeping with some of the compressed max loads. The powder pushed the bullets back out some unless they had a very heavy crimp. I also think he had to get a special seating stem to keep from crushing hollow point bullets with some loads they were so compressed.
I could be mis-'membering though.
Yes I did experience the bullet backing out with heavy compressed AA#9 (the older spherical microbeads) when trying to work with the Barnes 140 grain TAC-XP, 12.6 was all I could stuff...
Since I have been studying the pull-downs and powders it has been shown that Accurate Arms and Accurate powders under Western Powders now, have changed formulations over the years. #9 used to be 100% microbeads, now it is mostly a flattened ball powder. The forensic database http://www.ilrc.ucf.edu/powders/search.php (http://www.ilrc.ucf.edu/powders/search.php) showed several blends for #9
Accurate Arms-No. 9 New Blend
Ref#727 No 9 Blend 118/92 IMI No7 20%, WC 820 80%
Ref#739 No 9 Blend 106/94 WC820 90%, WC 350 10%
Ref#517
(http://www.ilrc.ucf.edu/powders/documents/powder%2000000517/SP_Ref__253_10x.jpg)
Ref#626
(http://www.ilrc.ucf.edu/powders/documents/powder%2000000626/SP_Ref__374_10x.jpg)
Ref#733
(http://www.ilrc.ucf.edu/powders/documents/powder%2000000830/SP_Ref__733_10x.jpg)
The newest formulation shown for Western Powder 10/26/15
(http://www.ilrc.ucf.edu/powders/documents/powder%2000000387/Powder_0000387.JPG)
This is why it makes powder identifications a little more difficult, but we can work through this easier with newer info. ;D
This is the older formulation for sure. (Said 11.99$) :o :o
CW
Quote from: The_Shadow on June 02 2017 09:35:40 AM MDT
Yes I did experience the bullet backing out with heavy compressed AA#9 (the older spherical microbeads) when trying to work with the Barnes 140 grain TAC-XP, 12.6 was all I could stuff...
Since I have been studying the pull-downs and powders it has been shown that Accurate Arms and Accurate powders under Western Powders now, have changed formulations over the years. #9 used to be 100% microbeads, now it is mostly a flattened ball powder. The forensic database http://www.ilrc.ucf.edu/powders/search.php (http://www.ilrc.ucf.edu/powders/search.php) showed several blends for #9
Accurate Arms-No. 9 New Blend
Ref#727 No 9 Blend 118/92 IMI No7 20%, WC 820 80%
Ref#739 No 9 Blend 106/94 WC820 90%, WC 350 10%
Ref#517
(http://www.ilrc.ucf.edu/powders/documents/powder%2000000517/SP_Ref__253_10x.jpg)
Ref#626
(http://www.ilrc.ucf.edu/powders/documents/powder%2000000626/SP_Ref__374_10x.jpg)
Ref#733
(http://www.ilrc.ucf.edu/powders/documents/powder%2000000830/SP_Ref__733_10x.jpg)
The newest formulation shown for Western Powder 10/26/15
(http://www.ilrc.ucf.edu/powders/documents/powder%2000000387/Powder_0000387.JPG)
This is why it makes powder identifications a little more difficult, but we can work through this easier with newer info. ;D
I found 13.0 g of AA#9 max for my reloads. Otherwise seating depth becomes a problem. with 200 grain XTP