I am wanting a block of steel or aluminum about like a loading block with 50 holes in it around .499 diameter, although I need to further research that dimension. Its purpose would be to serve sort of like a chamber checker to check the bore ride diameter of 500 S&W bullets I cast to make sure they are not too big around in the bore ride section. The holes have to be real precise as far as diameter and roundness. Anyone know who can make something like this? Thanks in advance.