I have a load that I developed from data that I found on the internet that I use with Remington 300 Grain HP. i think it would work with the Hornady 300 HP. I am going to try them next. The overall length will need to be adjusted for the difference in bullet length.

33.5 Grains H110
CCI 350 LPM Primers
2.020 COAL
1786 FPS through the Chrono at 15 feet.
2117.75 foot pounds of energy
543.25 Power Factor