I gave a 642 to a daughter that lives nearby when I bought one. I load 3.1gr Unique behind 147WC. Good, light, practice load. For carry we use 4.3gr Unique behind 148gr JHP, which we fire to clean up the lead, if any, from the wadcutters. There's truly no perceptible difference. But then my daughter has been shooting for almost 60 years. I don't see any sense in P+ loads personally. At the range where you might have to use it, the wadcutters would suffice. Further than that, get away!
