different makes of powder near same burn rate's

[Army-medic]

Use them to find an alternative powder with a similar burn rate. Then use the powder manufacturers load date or another reputable source and work up a safe load. Those charts are really handy, especially in light of many of the US Powders being banned in the EU recently.

[angrybear]

Buy the "one book/one calibre" for the round & it will list every powder load the various bullet manufacturers have tested.