Speer 135+P Golddot ammo
It's hard to find, but it has a great street record. Go online and search for it, or go to the Proarms website. They should have it. Mas Ayoob endorses this round highly. I shot this round last Saturday while out with my son and my dad. I fired it from a S&W that is just like the model 10 except it has an adjustable rear sight on it. I don't remember the model number. Anyways, your wife should be able to handle this round in your model 10. My dad's revolver also has a four inch bbl. Anyways, this round has an excellent street record in NY and LA. I shot it into milk containers/jugs filled with water. It was recovered in the third jug. It expanded to about .56 inch, and was a perfect looking expanded round. It's all I shoot out of my J Frame. Good luck with your choice.