Hi. An old Hornaday manuel I have lists 25.8 grs. with a HDY 158 HP pistol bullet at 2200 fps. For 1800 fps, try 21 grs. For 2000, try 23.4 grs. Remember to work up slowly, from well below. They start at 19.8 grs. for 1700 fps. These are for 2400 powder. They were developed in a Marlin 336 rifle. Hope this helps. E