Excellent article that deals with temperature stability of two Hodgdon Extreme powders, H4350 and Varget, and two IMR Enduron powders, 4166 and 4451.
A long read, but worth it. Reader's digest version: H4350 is the best with a mere 25 fps variation between temperatures of 25° F and 140° F, and IMR 4451 was the worst with 68 fps variation.
http://precisionrifleblog.com/2016/06/19/powder-temp-stability-hodgdon-extreme-vs-imr-enduron/
A long read, but worth it. Reader's digest version: H4350 is the best with a mere 25 fps variation between temperatures of 25° F and 140° F, and IMR 4451 was the worst with 68 fps variation.
http://precisionrifleblog.com/2016/06/19/powder-temp-stability-hodgdon-extreme-vs-imr-enduron/