Woodrow, I dont really remember why I went to 3.7 from 3.6gr. 3.7gr is still minor, I shoot IDPA; so not so much major & minor PFs back and forth. I have for the most part shot all the 155 plated bullets I had, now working with some Precision bullets. From them, I have some 155gr and 185gr; for the 155gr I was going to start with 3.3 grs and 2.8 for the 185gr. Those loads should but me close to where I want to be, chrono them and make adjustments as needed.
Once I get them chrono'ed I post results. Remember plated, moly and lead shoot differently, as do different barrels.