There are several things to consider when trying powders other than BlueDot and Unique. First, these powders are single based, usually meaning easier to ignite and less temperature sensitive. Note that I said less. 452AA and 473AA are double-based powders, more difficult to ignite and more temp sensitive. Second BD and Unique have a lower bulk density than the ball powders do, meaning that for the same charge weight they leave less airspace in the case than the ball powders do. This means that for the same charge weight, 452AA has 35% more airspace than BD. But then you will use less of the ball powder so depending on the charge weight they may occupy even less case volume with even more airspace.
Another consideration is position sensitivity. All powders are position sensitive to varying degrees, some more than others. I’ve used BlueDot in reduced loads for many years, and have demonstrated on the chronograph that both BD (and Unique) are position sensitive at 40-50% loading densities. Meaning, tipping the muzzle up before firing versus tipping it down results in velocity differences between 75 to 125 fps. This isn’t a lot, but it can mean a dangerous difference in max pressure between targeting a “flat” powder charge and shooting at a squirrel in a tree. I have no idea of the position sensitivity of the ball powders.
I’m not saying not to try them, just to be aware that there could be surprises in store. Just because two powders are close together on a burn rate chart doesn’t mean they can fulfill the same roles.
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Thank you for the well written response.
Mostly just thinking out loud, Seafire's post about different powders, thinking about other things than all the crap going on in this country.
My thinking on the 452aa is that it is very close to Bullseye. I know in 12ga you don't have to change anything on the loader and use either powder, at least by volume. 452 has slightly less velocity but not by enough to think about. Both great in the same pistol chamberings. Bullseye is used in cast and reduced rifle loads... just makes me go hmmmm about the 452.
Kent
