4.2 to 4.9 grs is standard in a lot of old manuals , while the
5.2 loading is a +P maximum load tested in a Universal Receiver
...........

otherwise known as a K frame or "Better".

5.0 grs of w231 with a cci primer in my J frame snub nose
kicked out 816fps but was also one of the "Widest" groups
in twelve powders that I tested.

5.0 grs of Universal, Unique or CFE may work better in the pressure dept. for you.