I got a surprise at the last Townsend shoot. I was repeatedly shooting over all the targets with my 6mmbr at 600 yards. This rifle shoots bug holes at these distances.
Then a little later as we were testing the magneto speed through my Oehler 35 the problem was reveiled. This rifle that shoots 107 smk's at 2775 fps in fall weather with a very low ES, was now shooting 2820 fps. Yep bitten by good ole RL15. This is the only rifle I still have shooting RL or IMR powders.
I will be changing it soon. I strive for first round hits at long range, this is where the temp sensitive powder have failed me and why I believe in Extreme powders. Now that I have a good chronograph I have been logging what they really do and I know why I like the H powders. It is right there in front of me.