When I used cast bullets in the 9mm I opted for the 147 gr to prevent leading. The W-W 14th edition reloading manual gave 3.5 gr. W-231 as max with that bullet at ca 900 fps. I used between 3.3 and 3.5 gr. for an accurate and soft shooting load with the 147 gr. cast lead bullet. A number of fellow shooters have experienced leading when attempting to use the lighter bullets and pushing them over 1000 fps.