I received reply regarding other compact magnums. They did not completely answer my question but partially did, only to say no testing on the 325 was forseeable:
"Given that we did not develop data for any of the IMR Enduron rifle powders it does not look good for this one."
Well, at least it kind of drops a clue for Staball's orignins- it's from IMR Enduron family....
Strangely, I see the Staball to be like Superformance v2; load data and performance is very similar for certain projectile weights.
Hodgdon didn't do anything but blow hot air up your arse.
StaBall is a ball powder from the St. Marks facility of General Dynamics, down in Florida. The "Enduron" line is from the General Dynamics facility up in Quebec. That facility was formerly owned by IMR, but in the past several years was completely rebuilt and revamped. Along with the updates came ingredient changes to lose some of the things on the various international "naughty lists". The updated formulations gave rise to marketing magic, known as "Enduron technology"....
Remember how they told you "they" created the awesomeness known as CFE223, from American Military tech? Yeah well, that powder is SMP-842, and was in production for well over a decade prior to them buying up all the surplus auctions. The base Tin ingredients used for copper cleaning, is French military tech from about 1900. Feel free to read about it in Hatcher's Notebook.... It's also been in Winchester branded ball powder since their inception in the 1930's. The addition of some Bismuth compounds is new tech, but it isn't US military; it's private defense contractor tech from GD.
Hodgdon does very little actual pressure testing "in-house", and a good portion (used to be most of) of what they test is with copper crushers. Those being somewhat more helpful than a magic eight ball, you won't get any data for something progressive (like Superformance).
If you want Superformance data, look in Hornady's manuals. Remember they hired Dave Emary(now ret). Dave was a powder tech for General Dynamics prior to them. Dave knows what he built, far better than Hodgdon knows what a lot of surplussed powder they bought; is capable of.
