I have an idea, Buy a safe, burn it and let us know if it survives or not.

The safe is replaceable it's the contents that count.Even at that Fireproof models are only good for so long in a fire. They have different fire ratings.Hopefully none of us will ever have to see how out safes hold up in a fire.Cannon's warranty covers fires and forcible entries.They even pay the freight back to the factory. Liberty warrants their safes against fire and forcible entry but you pay the shipping to the factory.So if you have one of these makes (probably others too?) you're covered for the safe. Contents are a different story.
Ruger Redhawk