That 56.5gn load with H4350 is quite mild. I would work up further. Most rifles will take several more grains.
That charge will only be generating around 2600fps, maybe a little more which is under the 2800-2850fps potential for a 180gn bullet in the .30/06.
Interesting, I get 2720 fps out of the 22" barreled featherweight and similar in the other 30 '06 I tried that load in. 57.5 grains of H4350 made the bolt pretty stiff to open in both guns. I was surprised that that was where the max was for my rifles but I have repeated the load enough times to be sure.
