waco, I have some experience with IMR 4198 @ 1,700 - 1,800 fps and Unique @ ~1,200 - 1.400 fps in my .30-06 with CB's between 140gr. (Lee TL group buy on Boolits site years ago) and 204gr. (Ly. #314299 @ .311"). For the plain base Lee TL bullet, I use 8.7gr. Unique because that's what my Lyman rotor throws: repeatably accurate. For gas checked CB's between 160gr. - 204gr., I use 12.5gr. Unique and get wonderful accuracy (also an excellent load for my Arg. Mauser and Finn. Nagant with #314299, sized to .313" and .312", respectively). 13.0gr. Unique is OK, but groups opened enough with that charge to make me drop back to 12.5gr. As for IMR 4198, 23 - 24gr. works well in the .30-06, but velocity is significantly higher, perhaps as high as 1,750fps using something like Ly. #314299. 18 - 20gr. will probably work, but I've never tried it, and thus won't suggest you do so.
One last thought: Blue Dot is another viable choice. With a plain base bullet 9.5gr. was the equal of 8.5 - 8.7gr. Unique. On the higher end, i.e., with gas checked bullets, 13 -14.5gr. would be a good place to start.