I can tell you that the extreme powders truly suck at -30-40 C, but so does everything else I tried.
I was in a bit of jam a few years back, I needed to give my load data to an Australian friend so he could load up a pile and have it waiting for me at that end. Trouble was, we were in the middle of a rather brisk -40 January. Hodgdon powders were the logical choice since the ADI equivilants were the most easily available to him which eliminated the load I was already using.
Long story shortened a bit, out of Hodgdon powders that were right at home
In 165 grain 30-06 loads Varget was the only one that would crack 2600 fps at 40 below. By the time
It warmed up to -20C they were only down 100, and relatively sane velocities returned at -10. Many of the powders traded places when things warmed up. Varget was the fastest at -40 but wasn't in the summer. That's OK, it wasn't supposed to be. H4350 is a classic at normal temps and sucked at -40.
I was in a bit of jam a few years back, I needed to give my load data to an Australian friend so he could load up a pile and have it waiting for me at that end. Trouble was, we were in the middle of a rather brisk -40 January. Hodgdon powders were the logical choice since the ADI equivilants were the most easily available to him which eliminated the load I was already using.
Long story shortened a bit, out of Hodgdon powders that were right at home
In 165 grain 30-06 loads Varget was the only one that would crack 2600 fps at 40 below. By the time
It warmed up to -20C they were only down 100, and relatively sane velocities returned at -10. Many of the powders traded places when things warmed up. Varget was the fastest at -40 but wasn't in the summer. That's OK, it wasn't supposed to be. H4350 is a classic at normal temps and sucked at -40.
