I am selecting either H900 or H1150 grade 17-4 to make some harder wear parts to replace a 303 piece. H900 runs about Rc 40, H1150 is around Rc 28. I'm wondering whether the difference between the two hardness specs means a complete change of tooling required. I need to make some disks about 1" dia. with a precision center bore and a few small holes, and I'm hoping that carbide drills are not required. It's small qty work on my own product, so I have some flexibility based on all the factors involved. Any guidance appreciated.