I got a redhead 1856 on sale at bass pro about 10 years ago for $599
dial combo, 23 gun. They loaded it on my truck, and I offloaded it myself in the garage. 490 pounds.
My first problem was getting this heavy bitch buried in the hole I wanted it mounted by myself. So I decided to take it completely apart. Removed the door, then the shelves. Then decided to get curious and removed the carpet (this was before I had the Jeep and the camper in the garage, and could take the cars out and really spread out)
I discovered the inside was nothing more than 2 layers of GWB on each side. So I removed those until it was just a bare metal box with no door. So I could move that with help from my teenage son. We set it in place and I then bolted it to the floor and wall with a series of washers that would prevent it being pried up/out unless an excavator ripped it out like that ATM heist
So now I had this empty metal shell mounted where I wanted it...what next? Well, I was working as a HVAC/Plumbing contractor at the time, and we were installing a massive hood in a retirement home kitchen. And out in the shop I had leftovers from the insulation and chase wall construction of those hoods. I figured, since I had an empty shell, THIS was the time to rebuild.
The safe I bought was only rated for an hour, but in the shop I had a whole roll of Pyroscat, 2 sheets of Type X and a sheet of Type C GWB. I had read that MOST gun safes had the GWB mounted right up against the metal, where an air gap was better for heat transfer. So I decided to cut that roll of Pyroscat up and line the entire safe with THAT first against the bare steal, and then 2 layers of Type X followed by a layer of Type C (because type X can get brittle and break off in chunks) and then reinstall the carpet. Once I did that I had to trim all the shelves for the added thickness I had created.
Got the shelves back in, then remounted the door.
No idea what rating it will achieve now, but it's better than it was.
About a year later I bought a stack-on 16 gun safe for my ammo and gave it the same pyroscat and GWB treatment. After talking to a couple of firefighters I know, they advised me to have all my ammo in a safe as well.