RL-22 is my favorite powder. I don't believe it has any more temp sensitivity than any other powder including the Hodgdon extreme series or IMR powders. I use RL-22 in 270, 280, 7mag, 7 STW, 300 win, 300 Wthby, 300 Jarrett, 338 Win, 338 RUM. It is a very versatile powder that seems to give top velocity and accuracy in most any calibur I have used it in. I do most of my load testing and development in Jan & Feb. usually early in the morning here in Va. The temps are usually in the 15-25 degree range with a few single digit temp days thrown in. I chro each round. When I find a promising load I load up 30-50 rounds and shoot them up in 3 shot groups thru the spring & summer. I specifically save many for the hottest days. Many are fired in 100 degree high humidity! Using this method I have yet to notice ANY significant changes in velocity, accuracy, or pressures during my testing with RL-22. Although my method is not perfect it seems to give me a very good reading on powder performance over a wide spread of temps. I've been doing this for quite a # of years and I'm sold on RL-22 as being one of the best powders available for big game cartridges in temps I am likely to hunt in. RL-22 has proven to me to consistently out perform every other powder I try using this method in accuracy, velocity, and consistency. YMMV, thanks 163bc
