In summary ... it sucks.
Short story ... I've gotten weird results with it that I've determined are due to Varget's ability to absorb water from the air, which is apparently tremendous.
Long story ... I bought a 22-250 in CO, and began making handloads immediately, using Varget since it's highly recommended, everywhere. They consistently chronyed 100-150 fps faster than the manual said. Multiple kinds of factory ammo were the same amount high, and my chamber passed the go/nogo guage test, so I assumed it was tight in diameter/etc and simply handloaded to lower velocities, to avoid high pressures. There were no high pressure signs though. This persisted over 4 different 1-lb containers (purchased at different times, so different lots) and there was no lot-to-lot difference. All of the reloads were very accurate and my standard dev were small.
Then I moved to TX (D/FW) and since there is no place to shoot PD and it's legal to hunt deer with them here, I switched to a heavier bullet (used 40 gr VMAX in CO), and started working on a new load. This is when the screwiness started. I expected to get 150 fps faster than the book said again, instead got a little below what it said or much below what it said, so 20-150 fps slower than the book, depending on when I made the loads. The standard dev stunk too, but the groups were still very tight, just centered all over the place at 100 yds.
So I posted here, and tried putting dessicant packs in the powder as was suggested. I figured more was better and put several of my home-made tea-bag/silica gel packets in the can, and put the can in a freezer bag with around a lb of loose dessicant, put the bag in a safe with a dehumidifier. I waited a month and reloaded, being careful to wait for a dry day, and then I exposed the powder very little, keeping the lid on my thrower, with packets in it, and seating the bullet right after I filled the case with powder (usually I seat them all at the end, after I've put in all of the powder). The results? It made no difference (the mean velocity was still 150 fps below what the book said and 300 fps below what I expected based on CO results), but the velocity actually decreased with increasing powder charge (seriously, and no I did not mix up the charges).
I spent a lot of time/effort/money eliminating various things like primers, following other suggestions, trying all this with the 40 gr bullets I used in CO too, then thought "you know self, we've always had great luck with IMR 4064 in our M1 and other '06, over the last 25 years, so let's just try it".
And, what do you know, the velocities from my IMR 4064 reloads (with both bullet weights) were about 100 fps faster than what the book suggested for that powder, just like the rifle got in CO with Varget. These loads were made with an old can of IMR 4064 that has spent its entire life in humid TX too. The standard dev were fine again, as were the groups.
My conclusions are a) if you want a powder you can use in a location more humid than Denver (which is everywhere except Denver), use IMR 4064, humidity doesn't bother it a bit, and b) don't bother with desicant packs, it doesn't help a bit.
I do appreciate that advice though, it sure sounded logical.
Short story ... I've gotten weird results with it that I've determined are due to Varget's ability to absorb water from the air, which is apparently tremendous.
Long story ... I bought a 22-250 in CO, and began making handloads immediately, using Varget since it's highly recommended, everywhere. They consistently chronyed 100-150 fps faster than the manual said. Multiple kinds of factory ammo were the same amount high, and my chamber passed the go/nogo guage test, so I assumed it was tight in diameter/etc and simply handloaded to lower velocities, to avoid high pressures. There were no high pressure signs though. This persisted over 4 different 1-lb containers (purchased at different times, so different lots) and there was no lot-to-lot difference. All of the reloads were very accurate and my standard dev were small.
Then I moved to TX (D/FW) and since there is no place to shoot PD and it's legal to hunt deer with them here, I switched to a heavier bullet (used 40 gr VMAX in CO), and started working on a new load. This is when the screwiness started. I expected to get 150 fps faster than the book said again, instead got a little below what it said or much below what it said, so 20-150 fps slower than the book, depending on when I made the loads. The standard dev stunk too, but the groups were still very tight, just centered all over the place at 100 yds.
So I posted here, and tried putting dessicant packs in the powder as was suggested. I figured more was better and put several of my home-made tea-bag/silica gel packets in the can, and put the can in a freezer bag with around a lb of loose dessicant, put the bag in a safe with a dehumidifier. I waited a month and reloaded, being careful to wait for a dry day, and then I exposed the powder very little, keeping the lid on my thrower, with packets in it, and seating the bullet right after I filled the case with powder (usually I seat them all at the end, after I've put in all of the powder). The results? It made no difference (the mean velocity was still 150 fps below what the book said and 300 fps below what I expected based on CO results), but the velocity actually decreased with increasing powder charge (seriously, and no I did not mix up the charges).
I spent a lot of time/effort/money eliminating various things like primers, following other suggestions, trying all this with the 40 gr bullets I used in CO too, then thought "you know self, we've always had great luck with IMR 4064 in our M1 and other '06, over the last 25 years, so let's just try it".
And, what do you know, the velocities from my IMR 4064 reloads (with both bullet weights) were about 100 fps faster than what the book suggested for that powder, just like the rifle got in CO with Varget. These loads were made with an old can of IMR 4064 that has spent its entire life in humid TX too. The standard dev were fine again, as were the groups.
My conclusions are a) if you want a powder you can use in a location more humid than Denver (which is everywhere except Denver), use IMR 4064, humidity doesn't bother it a bit, and b) don't bother with desicant packs, it doesn't help a bit.
I do appreciate that advice though, it sure sounded logical.
