fire damaged guns

[Shadowrider]

If only the plastic melted, I wouldn't be too concerned.
Most metals anneal in the 450-550 degree range depending on the alloy. Plastic at much less. Flash rust is probably from heat, and steam from the firehoses.
If the wood is scorched or burned, that is when I'd be concerned.
I'd shoot them.

No Dennis, you are thinking about tempering or a subcritical anneal both of which just make the steel non-brittle, and even if they did get that high this it would only make the steel more ductile, it won't hurt the yield or tensile strength. The temps you state are the start of the tempering range. To do a full anneal on 4140 which is what most non-stainless gun steel is you have to go much higher. IIRC over 1500, hold it there, and cool slowly. I seriously doubt that the temps got high enough for long enough to do any damage to the steels. I'd clean them up and shoot them.

 

[Honeybee]

I have restored lots of fire damaged guns, remember that's what I do for a living, and it would take a lot of heat to hurt them but fire is a funny beast.
If you ever make it to Tulsa then bring them by and I will give you a free estimate about their functionality and how to treat them.
For now just get plenty of oil on them, I prefer motor oil for fire damaged metal, it is a tougher oil than gun oil and will offer greater protection against further rust.

look for replacements for your melted parts at numrich gun parts.

 

[WTJ]

It appears that they may be ARs from the plastic? If you can find a portable Rockwell tester you may be able to check the AL for heat damage. I have done this with aircraft structure before. Not sure how that would work on steel. A conductivity test may be an option. Take a look at MIL-STD-1537C at everyspec.com.

 

[mr ed]

the locking lugs are about the only critical part. springs ,sears,and such can usually be easily replaced.
a commercial bolt gun will rockwell at around 30. military 98 mausers will rockwell as low as minus 10 and are still shootable. heat is not as critical as people think. watch youtube videos where people are shooting barrels to cherry red and they still work fine. you put a lot of heat welding on sights, barrel lugs, etc.
I put a mini-14 back together recently that I bought years ago from Walls fire store.(wish I had bought more as they had a shopping cart full of desert eagles)
plastic stock was melted. I just replaced the springs and it was good to go.
you have to worry more about them being hardened by quick cooling from the firehose than being too soft.
I'm rebuilding a burnt Ruger 77/22 and a marlin 39 right now.

 

[rhodesbe]

I took a picture of a fire-damaged glock I'm thinking about restoring. 3Gen, Austrian proofs, stippled backstraps:

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