For 30/06, I've had really good results with a cast lead 170 grain bullet from a Lee mould, with a gas check, using 16.5 grains Unique. The Lyman Cast Bullet manual shows this load should give 1811 Feet per second.
For some reason, the gas check makes all the difference for me to get a reduced velocity cast lead bullet to shoot to point of aim in my rifles. I bought some 165 grain .30 caliber cast lead bullets from Missouri Bullet Company, they had no gas checks, and at 50 yards they would hit 8-10" low, I didn't have enough elevation on my rear sight to get point of aim, point of impact hits. Using cast lead bullets with a gas check, I only have to raise the rear sight two steps in elevation to get 50 yard hits, with the rifle zeroed for factory jacketed ammo. This is the case for my 30/30 Winchester and my Browning 1895 30/06 lever rifle.
Beartooth Bullets offer a selection of .30 caliber cast lead bullets with a gas check.
Casting your own is very satisfying, and can get your cost per round below .10 cents per round.....