I think .200-.250? For sure, .320 will feel like a brick in hand, if brick can cut... Flipping'll be damned though...What was the original war boar thickness? .32 would be sexy as hell.
With that thickness, might as well go balls to the walls, and make the blade 5 inches, making it the... Giant War Hog?

I'm drooling at the thought though, a big freaking karambit in INFI...