The issue of which powders are the same is that the same company may produce the different powders but the chemical mix, coatings change the way it burns so that they maybe very close but not exactly the same.
The rate at which they burn can be similar as is found when one buys surplus powders from military salvage sources and what they tell you to use as loading guidelines.
I don't think you will ever find an exact cross reference as each lot of a given powder is close to the original design but there are still differences and it is up to us the end user to pay attention to lot to lot differences. While these differences are minor and are not really something we have to worry about it does happen.
my .03 cents on the subject