IMR 4064 is a great powder for 30-06, 308 and a number of cartridges. You might want to consider my thoughts on this subject. I average shooting over 200 rounds of Contender and Encore rounds a week. Muzzle blast and recoil are major concerns to me. I cant handle too many blasts that nearly set my beard on fire before I start backing away as I pull the trigger. It is frequently declared in my circle of shooting friends that if a gun will not shoot with 4064 powder, it will not shoot with any powder. I would start with 4064 and use that as a standard of expectation while looking for a load that produces less blast and recoil.
Consider 48 grains of IMR 4064 behind a Sierra 165 grain bullet seated to an OAL of 3.23. (I always insist that at least a bore diameter length of the bearing surface is inside the neck of the case. Example: if the boat tail is .2 long on a .308 bullet, then I seat the bullet down .40 to provide alignment for the bullet in the case. In this example I seated the bullet .46 into the case.)
This load will produce 2333 fps from a 15 barrel and burn 94.11% of the powder in the barrel with a 22.4% ballistic efficiency rating. This is very acceptable, but there will be some muzzle blast.
Now, consider using 45.7 grains of IMR 3031 with everything being the same. The velocity from the 15 barrel will be about 2400 fps. 99.75% of the faster burning powder will burn in a 15 barrel and produce virtually no blast out the barrel. The ballistic efficiency of the load is 24.9%, which is very acceptable. The recoil will be around 20 foot-pounds of energy with both loads.
The less powder that burns outside of the barrel, the less lip flapping, beard burning muzzle blast you will encounter.
At 200 yards, the bullet will still be going 2002 fps with 1474 foot pounds of energy with the IMR 3031 loading.
If you have access to a 48th Edition of Lymans Reloading Handbook, check out the Encore section for 30-06. You will note that they list much faster burning powders for the 15 barrels. Example: IMR 3031, AA2460, IMR 4895, WW 748, SR 4759 and XMP 5477 for the 170 grain bullets.
Please note that the listed loads above are only suggestions for the purpose of studying muzzle blast and efficiency. I would not hesitate to use either of them in my Encore, but you should start several grains lower and work your way up while watching for pressure signs.
I hope this gives you something to consider.
Harold Clark