Yes use Red Dot data.
Great powder my favorite in 45 Auto.
Fine in 38 Special too.
If the price is good go for it.
You will be good through the next panic or two.
Call Alliant to be sure. They are very helpful. They say on their website it can be used for hand gun loads. They have to have some load data to say that, just haven't published it yet.
I've also heard that it's a cheap Red Dot but never used it.
It is like Red Dot but...................
was a "Promotion" powder to get people into shooting Alliant powder.
Mainly as a shotgun powder and the loader was "Advised" to use the correct powder Bushing with Promo since it was not the same as Red Dot in its make up.
Standard procedure was to drop down two sizes of Bushing, smaller in size.
Red Dot without the dots, basically. Measure it by weight, as others have said, and you'll be fine. 2 1/2 To 3 grains of RD with a 158 grain bullet works well for me in .38 Special.
Promo was developed as an economical powder for shotshell loading
for clay bird shooters. Red Dot has long been a very popular powder
for that purpose. Promo loads with Red Dot data but is a bit more
dense which wouldn't bother handgun loaders but shotshell loaders
mostly use fixed charge bushings. So Alliant makes note of the need
to change bushings when changing powders. Many shotgunners have
embraced Promo because it's cheaper than Red Dot and is sold
only in the 8 lb jugs to keep the cost per lb down.