In Lyman's old manual (44th ed.), there are several loads for Herco in .357 that use pretty large amounts of powder, even some compressed loads. For example, a number of CB loads in the old Lyman manual show max loads of Herco of over 11 gr for bullets from 121-158 gr (p117 of the 44th ed.) The latest Lyman man. (49th ed.) has nothing over 8 grains max, and the starting loads are much lower, too.
What changed? Has Herco been reformulated? Shotshell reloaders' conventional wisdom is that it hasn't changed at all in our lifetime. Have the manuals simply gotten more conservative in the face of liability concerns?