I've been using 56.0 gr's IMR 4350 for Hornady's 165 gr Interlock and have no reason to change.
I use that powder for 270,30/06,300 Win Mag and 300 Weatherby Mag.
I have used Reloader 17 with good results but since IMR 4350 has been back on the market for the past few years I stick with that.