Different powder burn rates

[Seabeeken]

Burn rate also changes with different cartridges, bore diameters, etc. I have several N-150 and 140 powder models in GRT that are calibrated to various cartridges. Same with other powders also.

 

[johngibbs222]

I looked at Norma's data, they have a handy table - https://www.norma-ammunition.com/en-us/reloading-data - I'd say read the instructions untilyou get what they are trying to say and you may find it helpful.