H4350 and the more recent sibling RL17 are THE best powders for velocity with the .30/06.
However, in my experience, the original IMR4350 still beats them both for accuracy.
My "accuracy" load dating to the mid '70's with my MkX .30/06 was the Sierra 165gr BTHpt (now called "GameKing") over 56.5gr of IMR4350 yeilded 2,775fps for 3-shot 1-hole groups.
Lately, I'm using the 165gr Nosler Ballistic Tip over 57.0gr of IMR4350 for 2,830fps from a Colt Lt.Rifle for ~.70" 5-shot groups. Drop to 55.0gr for a 180gr Nosler B.T. or Sierra GameKing BtSpt. for 2,770fps. (24"bbl).
I'm now using 57.0gr of RL17 w/165gr N.B.T. and Sierra G.K. for 3,000fps but "only" about 1moa....... hah! I'll take the "loss" of accuracy for 200fps !!!! My older brother uses the Hornady 165gr SST from his 22" bbl circa 1971 Rem Mod700 and 58.0gr of H4350 for ~1.2moa and 2,900fps (22"bbl). These are "long range elk loads"...... Not target loads....
But, he won't let those load within 30' of his National Match M-1 Garand. He personally knows a shooter/competitor who bent an op-rod by "accidentally" shooting a 168gr BtSpt loaded with that load of H4350......
For the gas-auto's, stick with IMR-4895 or IMR-4064 (a favorite for 150gr bullets...).