will the firearms/ammo still be safe to use after being exposed to extreme heat?

debating on getting a fire lined safe. high priced valuables im planning on storing in an ammo can that has ben fire-lined vs lining the whole safe

I'd say it's one of those intensity vs time thinks there would be no set standard/answer. All of the following metals Aluminum, Steel, Stainless Steel are all alloyed by each manufacturer heat temperature (intensity) and time can change the molecular structure   (Tempering) causing the metal to loose strength or to become harder and more brittle. I have a thread about a safe and another member posted if your house were to burn how worried would you be about just your firearms?

Edit/addition-I see you posted in the thread I was referring to above. Below is zippz comment I tried to paraphrase above.

I'm not a fire expert, but I'd assume 30 minutes of fire protection is usually enough.  Probably doesn't take that long for a house to burn down, and even if it did your homeowners insurance should cover the cost of the loss if it's documented.  And saving your guns would probably be the least of your worries anyways unless you had rare antiques.

So what safe have you decided on or what's on your short list?

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I know I could throw a mosin INTO the fire, and it will still work. LOL

You would be better off leaving it in the fire. 

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