Well as most of you know, Badnews Bob and I just got back a couple days ago with our first batches of surplus powder to try out. I loaded up 9 357 Max with the AA1680 equivalent and 180gr SSPs for groups later and one extra just to shoot tonight to see how it shot.
The load range for that bullet according to the info at the Accurate site is 23.9 - 26.5gr. I decided to start on the mild side of the middle with 25.0gr. Whew ! I fired that extra load I made and that primer was flat, real flat, not flowing into the firing pin hole but much hotter than I normally load.
No harm done, but the moral of the story for those dabbling with them is:
Surplus powder equivalents are not "equivalents", they are "approximates". Start at the bottom, mildest, STARTING loads and work up. (that seems to be a repeating theme that I have repeatedly ignored with commercial powder unfortunately)
Shoot safe,
Ian