When deciding on a shotgun action for a double rifle build, what do you guys look for? What makes one unsuitable etc?

Ive got this 16 gauge R.Redman with damascus barrels, apart from the stock its in alright condition, actions fairly tight (IMO). One day I wouldnt mind having a .360 2 1/4" made on it if its doable.. (Ive only seen Cartridges of the Worlds listings for its performances, but what were its loads?)

Cheers,
Troy.