Hi Bluedot37, thanks for the welcome.
You are correct. There are only the standard published burn rate charts, based on a standard sized "vessel". To test, compile and publish them for all the various cartridge case and bullet combinations would be impossible. However, it is a fact that powders can change their relative burn rate order based upon the cartridge case they are used in and the bullet behind which they are used. This is sometimes explained in the verbiage that accompanies standard charts.
As a matter of fact, Dick Lee (founder of Lee Precision) reported that INCREASING the charge weight of powder in the same powder/case/bullet combination to a point where the powder becomes compressed (by seating the bullet deeper), can actually LOWER the pressure (compared to lighter weight charges), in effect making the powder change its burn rate to a higher (slower) number. He demonstrated this using IMR3031 and 110 gr bullets in the 30-06. You can read about this on pages 100 and 101 in "Modern Reloading by Richard Lee". My copy was printed in 2001.
So, bottom line, burn rate charts are approximations and powders can change their relative positions based upon various factors.
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