Reloder 22 is a great powder in the 7mm RM for the temperatures you hunt in. If it's working for your rifle, I wouldn't change it.
Temp-resistant powders are really only useful when temperatures range 100 degrees or more, and even then may only make a difference at ranges beyond 300 yards, which is as far as most hunters tend to shoot.
If you want some recommendations for other powders I can provide 'em, but it's hard to beat RL-22 for your purposes.
I'm not sure if I'm understanding you right. If you worked up a load with RL-22 on a 60* day, are you saying that it wouldn't be an issue down to -10* or up to 110*? (so it would be + or - 50* for a total of 100 temp range)
Or are you saying that it would only be an issue if temps were above 100*?
