The 49th and 50th Lyman manuals show 3.7gr-4.2gr of Unique running over 800fps throughout that range. It appears that I loaded the Berry's with the HB forward at the top of that range. No doubt in some fit of nostalgia. I also loaded a lot of BBWC using Unique, with no notes of why I felt 800+fps was necessary.
My AA5 data is so old they have certainly changed it.
TiteGroup and WST data can be found on Hodgdon and Alliant's sites, and I've stayed with starting loads with those powders, mainly for J frame practice ammo.
"Gunfighting is a thinking man's game. So we might want to bring thinking back into it."-MDFA
Beware of my temper, and the dog that I've found...
You are correct, it is very general.
I treat almost any plated bullet as a swaged lead bullet because that's what the vast majority of them are. They are just dead soft lead, swaged, and with a thin coating of copper electroplated over them and probably sized again after plating. I'd treat the X-Treme WCs the same as Hornady or Precision Delta lead but you don't have to worry about the skirt since there isn't one. The ACME DEWC will handle far more pressure if that's where you want to go due to being a hardcast. My load is 3.0 grains of WST. They shoot plenty good for J frame practice which is what I use them for.