Originally Posted by CasualShooter
I found this chart, which is pretty comprehensive, but suggest it is only a general guideline.

http://www.adi-powders.com.au/handloaders/equivalents.asp


That's just a relative burn speed chart simplified. It list powders by the neighborhood method.
Note it puts IMR-4895 on the same line as H4895. When you look at Hodgdon/IMR's own data, you'll see they are not the same and you can't just swap one for the other.