If your rifle shoots to the same place with the RL-26 load at various temperatures, then there's no problem. As I mentioned in my other post, some rifles don't show any shift in POI even with a 100 fps change in muzzle velocity. Others will will only 50-60 fps change.
Might also mention that Magpro is not particularly temperature-resistant, either in my experience or that of the ballistic lab guys who worked at Western Powders before Hodgdon bought the company.
