Yes all true and I do think there is something to cartridge efficiency but not sure what it is. One article I read showed that there was no difference in velocity between different neck configurations but they stopped short on testing pressure/velocity uniformity which things do seem to indicate certain designs contribute to more uniformity. Look at the PPCs and other short-fat rounds and with a 30 degree necks there does seem to be an improvement in uniformity.
Also accuracy nodes or windows seem to run across the board in spite of which cartridge it is fired from. Certain bullets esp. VLD types will run best at say 2900 fps and it does not matter which case they are shot out of even if that case could go to 3,200 fps.
I wish I had accurate strain or pressure equipment. If I did I bet the 101 year old Swede at 65,000 psi could give the .264 Winchester a reason to look over it's shoulder to see what was breathing down it's neck.
"When you disarm the people, you commence to offend them and show that you distrust them either through cowardice or lack of confidence, and both of these opinions generate hatred." Niccolo Machiavelli
