Great questions. First off a list of powders. For 12 GA:
IMR-700x
Clays
International Clays
Clay Dot (Alliant Equivalent of Clays)
Red Dot
Promo (1970 Formulation of Red Dot, highter density so smaller bushing is used to get the same weight)
Green Dot
Winchester WST, WSF
Unique
I just got 16 lbs of 700x as it is also the powder I use in my .45 reloads that I sell. I did it by placing a backorder for it at MidSouth Shooters Supply. The order shipped three weeks after I placed it.
Before you order, look at your load data and make sure you have data, wads and hulls that all match. A good source of shotgun data for hulls like Rio, Fiochii and Chedite is Ballistic Products. BP has pages and pages of it and not much on Win-AA, Fed GM and Rem STS. Lyman is a better source there, but the BP wads as so much better in terms of performance and they are the same price or lower than what you will see for WAA12xx kinds of wads including Claybusters.
IMR-700x
Clays
International Clays
Clay Dot (Alliant Equivalent of Clays)
Red Dot
Promo (1970 Formulation of Red Dot, highter density so smaller bushing is used to get the same weight)
Green Dot
Winchester WST, WSF
Unique
I just got 16 lbs of 700x as it is also the powder I use in my .45 reloads that I sell. I did it by placing a backorder for it at MidSouth Shooters Supply. The order shipped three weeks after I placed it.
Before you order, look at your load data and make sure you have data, wads and hulls that all match. A good source of shotgun data for hulls like Rio, Fiochii and Chedite is Ballistic Products. BP has pages and pages of it and not much on Win-AA, Fed GM and Rem STS. Lyman is a better source there, but the BP wads as so much better in terms of performance and they are the same price or lower than what you will see for WAA12xx kinds of wads including Claybusters.