Not part of your problem but tupperware generates static electricity. Doesn't mix sell with 8lbs of powder. Next time pour 1 lb into your half full 8lber and roll it around, it will mix fine, Do it with all the 1lb containers. Modern day powder containers are designed to not generate static electricity.I've had about .01 throat erosion. Not crazy bad.
I've tested both virgin and once fired brass and get VERY similar velocities. Within 10 FPS. My fired brass is only .002 larger than virgin brass and I basically FL size it back to virgin measurements.
So with the powder. I had an original 8lb keg. I got down to about 4lbs and bought four 1lbers from a buddy. I poured all 8lbs into a big tuperware and mixed it all thoroughly. Then put the "new lot" back into the 8lb jug. This would lead me to believe this is 100% the culprit BUT my old loads that I loaded with the very original 8lb now shoot considerably slower. Could the powder be settling in the case over time and just not taking up as much volume? Also, I stay out of the lands.
Probably NOT, too "Wild of, a "Guess", as most, overbore, Hot Magum, Barrels only last,.. 700 to 900 rounds !Best wild guess- Throat erosion
The 28 nolser has pretty wicked throat erosion especially with n570.
Has your cbt lands measurement changed?
No it makes total sense haha. Basically my exact scenario!In my .300 win with 215’s my original load with virgin brass and powder lot #1 was 4.5-5 gr less than my last load. I was on 3x fired brass and a new powder lot.. I had 2 increases in powder.. one increase was from virgin brass to 1x fired.. then I switched lots of powder between 2xand3x firing.. that made me increase powder charge again..
If this doesn’t make any sense i apologize, I’m in the hospital and they’ve got me on some good stuff ... I tried to make sense
no, it won't increase the pressure just a more consistent release of the bullet it improved my groups and numbers went down as well follow the directions and you be all set you don't need a heavy crimp just enough will doI ordered one to test out! Do you normally need to drop powder charge when crimping vs not crimping? For pressure related reasons?
Thank you for the insight! I read the butter bean thread. Probably just start with an 1/8 turn and see how she doesno, it won't increase the pressure just a more consistent release of the bullet it improved my groups and numbers went down as well follow the directions and you be all set you don't need a heavy crimp just enough will do