Have you had any experience with overbore cartridges? If you can lay your hands on P.O. Ackley's books, he has written about this condition. In addition to bolt face concerns, what about magazine modifications?
If I were out to do such a thing, I'd get measurements from your .223 bolt and any Weatherby Magnum bolt. If they're the same diameter, then what you're out to do is probably do-able, albeit crazy IMO.