Re: R25 being to temperature sensitive.
The RL powders last couple years have run into some real problems lot to lot with varied burning speed. they have posted warnings on their website about one lot of RL 22 in particular. IF you want to use the RL powders you would be advised to get the 8lb kegs so you can work up loads for one lot for awhile. Otherwise it is often too hard to find enough of one lot that works. I switched to Norma MRP for that reason in my 6.5/06AI. Same speed as RL 22 and no variance in lot to lot, comes into Graf and Sons once a year and we order large quantities of all some lot. They also now have MRP2 which is supposed to be similar to RL25/H1000 etc.