No direct experience but will suggest that you just use handgun data and work up from starting loads toward max (watching for pressure signs, etc, etc) while shooting off the bench at the full 200 yds. This is a pretty slow powder in .357, right? The only message is that you seldom see any real difference in the good recipes for rifle vs. pistol in the straight-walled pistol cartridges (or, for that matter, in the bottle-neck rifle cartridges.) What works well in the short barrel should work well in the long one. I do believe the 92 is known as a strong action. Good luck.