@metengr the spectroscopic gun is extremely accurate (and is calibrated) in identifying the chemical composition which I've listed in the first post. If you know the commercial name, feel free to chime in with your gems of knowledge. Thank you!
@EdStainless
I don't have the hardness of the material and no more material remaining, other than chips from machining. At this moment the hardness does not interest me much since the 20 or so parts have been made and are in the hands of the customer. If this job comes to us again, we'll do a hardness test. But I'm more interested in the type of steel it is, so that we don't break expensive inserts and tools. Someone told me that this could be 17-4PH, but this has Vanadium as well as a generous amount of Ni, which is not in 17-4PH. The issue is that all aerospace parts come with a detailed spec sheet of each raw block, this one was not an aerospace part and the paperwork didn't have any details of the material except: X5CrNi18-10 (aust. 304) written on the drawing. It is clearly not 304 from both the spectroscopic analysis as well as the way it ate up the 304 specific inserts. If you have an idea of the material, that's great but if not, I've got the message around my networks and someone should chime in.