said by Zach1:
A picture would be most helpful in confirming what type of cable was used to run the existing circuit. From the description (B-W-bare) it's two-conductor with ground NM (Romex). It was never code-compliant to use the bare equipment grounding conductor in NM (Romex) to feed dryers/ranges where the frame is bonded to the neutral. The only cable with an uninsulated neutral permitted for 3-wire range and dryer circuits was type SE. Since the original circuit was never code-compliant and "grandfathering" doesn't apply, it must be replaced with a properly sized 4-wire circuit.
Unless the previous range operated at 240v only and did not require a neutral. If it had a timer, clock, or an outlet that's probably not the case though.
Without at least pictures in this case, saying what is or isn't code or grandfathered is just guessing.