Will I need to flare to 30-06 cases so I don't shave lead or powder coat as well?
Yes, you should. don't know about powder coat bullets, I don't use them, but regular cast lubricated bullets do best when the case mouth is slightly flared allowing you to start the bullet base in the case.
A VERY "generous" chamber may produce acceptable results with mininal shaving, or not, it all depends on the details.
The best way to load cast rifle bullets is exactly the same way you load cast pistol bullets. Belling or flaring the case mouth slightly to allow the bullet to start into the case straight and without the case mouth shaving anything off the bullet.
For cast in the .30-06 the best thing I can recommend is the Lyman "M" die and a .30 expander stem for it.
The Lyman expander plug is very good, because it is a two level thing. The lower part is sized to ensure the case neck inside is the right diameter, and the upper part is a "step" larger made to flare the case mouth/
Proper adjustment is needed. The die can be set to flare way too much, and even crack the case mouth from overexpansion. SO, read and follow the instructions, its not difficult but you DO need to start with less and do test runs as you adjust.
If you have Lyman 3 die pistol set, you already have an "M" die ("M" is the Lyman designation for an open die body, it does not touch the case, it just holds the expander stem), so all you will need is the .30 cal expander then swap the pistol expander for the .30 one install in your press and adjust with a sized case.
If you use other brands I can't help you with the details, I use Lyman, mostly. I do know some other brands use an expander with a constant taper, while Lyman's have a clear "step".
Get an M die and the right caliber expander for what you're going to load, you won't regret it.