What powder to copy the Hornady 123gr AMAX? What else would I need to do?

[bwaites]

Hornady is using a powder and load specifically developed for the Grendel. It is believed to be along the lines of the Superperformance powder, but no one is actually willing to admit that it is the same powder recently released by Hodgdon as Superperformance. I intend on trying some, but it is shown to be fairly slow, closer to the 4831 line, used for Magnum and large cartridge loadings, than to the powders typically associated with the Grendel like BLC2, etc.

They tailored the burn rate, pressure curve, etc. specifically for the cartridge, supposedly.

Interestingly, the Leverlution powder is closer in burn rate to BLC2, but I haven't found either powder yet locally, so I don't know if they are ball or extruded, big or small, etc.