Sorry to burst your bubble....
Whilst IMR 8208 is marketed as an IMR powder, as others have said, it is made in Australia as part of the Hodgdon 'Extreme' line.
The closest to what I would call BM 8208 is either BM2 or AR2206H. That would be XBR8208, BENCHMARK and H4895 respectively.
AR2208 (Varget) is a bit slower than AR2206H (H4895) and has a much lower loading density (weight for volume).
I also use Quickload and it is a useful tool - but not an absolute.
You may want to look at this equivalence chart (published by the manufacturer).
Powder equivalents Note: This table shows only approximate equivalent values within about 5%. Actual burning rates can vary depending on the calibre, firearm, loading components and practices, as well as from powder lot to lot. As a consequence, it must be understood that Australian Munitions...
www.adiworldclass.com.au
And this article on production frequency.
Dear Sporting Shooters, It has been quite some time since our last propellant update. We would like to assure you, the factory continues to run at maximum capacity, 24 hours a day, 5 days a week, and we’re supplying as much propellant to the market as possible. Any difficulty in accessing our...
www.adiworldclass.com.au
The key thing this chart says is this:
Note: This table shows only approximate equivalent values within about 5%. Actual burning rates can vary depending on the calibre, firearm, loading components and practices, as well as from powder lot to lot.
So, if you have a lot of varget that's plus or minus 5% or a lot of H-4895 or IMR 8208 BXR thats plus or minus 5%, they can all be very close to
one another. The chart is not absolutely definitive as to burn rate or ranking.
But, I did very closely examine Varget, H-4895, and Imr 8208 BXR in Quick Load, and what I found is that the ranking by Ba from QL may in an instance where a powder has a very high deviation in Degressivity Factor AND the Ba factors are very close, may give mixed results.
The Degressivity Factor in QL accounts for the change in surface area of the powder granules as they burn. Varget has a very low Degressivity factor compared to 4895 and 8208. Therefore what I think is going on is even though Varget has a higher Ba factor in QL, it may in fact have a lower over all burn rate due to the shape of its granules and the effect that has on the surface area burning during ignition and over the time of the explosion.
So, depending on the lot, the primers used, the overall COAL and size bullet, the length of the barrel, and caliber loaded, the burn chart may vary and the Ba factor from QL may also not always be definitive as to ranking when the Ba's are very close ----but the powder shapes and burning characters are very different--- as in the grouping of 8208, H-4895, or Varget.
All of these factors are accounted for in QL, as you can see that both
H-4895 and 8208 BXR will predict higher velocities for the same grains of powder vs. Varget which will be slower, evidently due to its granule shape and burn degressivity character.
Its also why we use loading manuals with actual data to go by, and loads are worked from the bottom up. I personally still get more definition and appreciation for how close powders are to one another using the rankings out of QL but apparently powder shapes and burn characters can also affect those expectations too.
