Your question is about the same as "What does the color blue smell like?".
Provide details and better yet some pictures to go with it. Not all gun safes are fire proof for example - how much heat do the mattressbacks think was applied to your firearms and for how long. Wood charred?
Moisture from firefighting? Were the firearms at least washed off and dried ASAP or are they still sitting in the safe in moisture, mouldering?
The more details you can provide about the more help you're more likely to get.