25-06 6.5-06 and 6.5-284 all have a case capacity that is about 1 or 1.5 grains of H2O difference from each other. They should all use a similar burn rate. I would never have considered using some of the slow powders that 25-06 shooters are using in my 6.5-284. They are claiming excellent results with Retumbo. Looks like i need to get more open minded about these kinds of things.