Suggest starting at 4.0 grains of WW231. Max charge of WW231 with bullets of this weight is typically 4.5 grains.
If you haven't already picked up the powder, I'd suggest looking at PowerPistol. Start at 6.0 grains and work your way up. 6.7 grains is a typical max. load. I really like PowerPistol in 9mm and .357 Sig loads.
Both sets of data listed use an OAL of 1.125 inches.
Don't want to guess, call Hornady directly on the 800 number listed on their website. Listening to their phone menu is worth the call. They have and will furnish any data you desire concerning the performance of their product with various powders. Very good people to deal with.
Take Care