Looks like you have a load to reach your goal of 1K fps.

When I want to practice with magnum velocity lead bullet loads in the .357 I use .357 cases and hard cast bullets with 12 grs of AA9 or 13grs of 2400 for 1,200 fps +.

For practice using .38 spl loads with the softer Speer swagged bullets they usually get loaded with Unique or W231 but currently I'm burning a keg of Green Dot bought at an estate sale and don't worry about reaching a particular velocity.