My experience is that you seem to need about 850 fps to get 158 LSWCHPs to open up. Not bad recoil, but not plinking either. Of course from a 3" that will not take as a hot a load as required in a 2"
I think the best overall .38 bullet is probably the 135 gold dot. I have shot it at many different velocities, from 900 fps to 1300 fps and it doesn't care how fast you drive it-- it holds together well and expands with very sharp cutting edges to about 0.60. It doesn't get any bigger when you drive it faster-- it just goes deeper. It's a very predictable bullet.
The remington 125gr golden sabers were available super cheap for a while. They open up around 900 fps, get very big and sharp and cut well. Only downside is that as you drive this bullet faster you get more expansion rather than more penetration. At 1100 fps they still held together but opened up to about .75 as I remember. Very sharp edges and definitely cutting a .75 hole.
What might make the decision in the end is what the sights are regulated for.
Wadcutters are also fine but in a 3" you can definitely squeeze enough velocity out to make an expanding bullet work. Big difference between a .75 or .60 hole and a .358 hole.
