Bnhpr
OK, Bnhpr, I dug out my lone specimen of the 30 TC and took some measurements.
As Larry said, the shoulder angle is 30, not 20, degrees. The shoulder diameter is .461, far bigger than the 308W case at the same location.
So, to answer your question. No.
Why not talk with some of the HBR shooters like Al Nyhus, Randy Robinett, and Stan Ware. One of them probably has a 30x47, 30x48, or 30x49 reamer, or something close to it, and Stan would probably do the work for you. Of course, it will be a wildcat and you'll have to make brass.
Otherwise you'll have to get a 30 TC reamer, if that's the exact cartridge that you want.
Ray