The .222 rem mag intrigues me, and I think it would work, but still lighter than I want to deer hunt with.
Rebarrelling a working 223 to 222 Remington Mag would be insane. I know 223 is a bit hard to find right now
, but the 222 RM is nearly obsolete. The only one still making it is Nosler Custom at almost $2 a round.
I agree both are light for deer.