PS: Does anyone know what powder Hornady uses in its cartridges? Is is proprietary
That's a good question. I wanted to replicate some winchester rounds,,I pulled a bullet and the powder was a duplex mix. It had Ball and Flake powders in the mix.
Hornady must be using their "Match" bullet, so that's easy enough too get,,Then it's kinda just a matter of funding a hot burning powder to get the velocity
YOUR rifle likes. You already have an OAL that works so it's just the powder. My 223 likes varget,, but I don't think it'll give you that velocity.
Maybe someone out there has a Hornady book that can look it up for ya,,,