If you are making "Target" rounds use Factory ammo as a template or standard for your numbers;
Federal "American Eagle" Factory Ammunition
124g RN FMJ
Velocity - Box listed @ 1,150 fps /1,121.4 fps my 5 shot average @ 73 degrees
OAL - 1.150"
The Hodgdon Reloading annual 2012 has listed for the 124g FMJ bullet;
WSF - 4.7g up to 5.3g (max vel. of 1,115 fps) - they show testing this out of a 4" barrel.
WSF powder is a "medium" burning powder (#36 on the Hodgdon burn rate chart) which means - in my tests with 115g FMJ bullets, the powder charge on the med/high side worked out the best for me out of my G17 w/4.49" barrel.
Most of my tests using 124g FMJ bullets with med/slower powders work best at an OAL of 1.135" Not the 1.169" listed in the Hodgdon Annual. Now again that's out of my G17... not your pistol.
Start low and work up slowly with charge weight and OAL until you find out what your gun likes the best.
I hope this will help you, good luck & be safe.
"A man can never have too much red wine, too many books, or too much ammunition"