What I did for KYHillChick with her SP101 was do a reverse version of the ladder-- 5 rounds each reducing the load .2 grains at each step. When we got about halfway between a 357 Mag and a 38 SPL she said that was perfect. She and I both shoot 357 mag, but hers is just a tad lighter than my LCR load.
We were using 125 grain Hornady XTP's and Universal. Both loads ended up faster than a Fiocchi self-defense load in 38spl +P that I'd used as a benchmark. That load used XTP's as well.
