I'm looking for a listing of stable powders that will have minimal fluctuation of pressure due to outside temp. Typical load development around 80 degress with hunting any where from 20 to 40 degrees. Powders will be used in 300WSM. Oh, i read the suggestion of using dry ice, no thanks. Thanks

Take a look at Hodgdon's "Extreme" line of powders.

A second to craigster's recommendation. And, in the 300 WSM, H4350 is usually a pretty good fit, at least with 150 and heavier bullets.

R-WEST