My Father in law had a fire in his 5th wheel trailer, and in the fire was this S&W 66-4 2.5". You can see the black rubber leftovers of the Hogue grip on the bottom, you can still see the texture of the rubber grip in many places. The other side is actually better looking with a lot of shiny metal and not a lot of rust anywhere, looks to me like mostly drippings that melted to the gun. Everything is locked up tight except the cylinder that will wiggle a little but not open. I contacted Smith and they said they do not deal with guns that have been through a fire. I do not know how hot it got either.

Is this something that can be salvaged or is it just a paperweight at this point?

Some company will actually test the gun to see if the metal is still safe. I can't remember the name off hand.

Probably depends on how hot and how long it burned.

If it were mine, I'd strip it down, give it a good twice over cleaning, replace the grips and springs then pretend like nothing happened.  If I had reason to believe heat may have compromised the steel's integrity, I'd load a round for each cylinder, about 10% over max, trap it on my shooting table with a few sandbags with a string around the trigger and let her fly.  

But since its not mine, I'd suggest you find a LGS to do the above for you.

ETA:
Damage to the springs is a good indication of heat levels and time.  

Is he an NRA member? The NRA firearm insurance that comes free with membership will cover loss due to fire. You have $2500 worth of free coverage with your NRA membership.

The problem with a fire involved item is you have no way of knowing how hot it got and for how long. Enough heat will draw the carbon from the steel, rendering it to damn near pig iron.

The exterior of the metal will be scaled if it got that hot. OP should clean the gun up so he can have a better idea of it's condition.

Working on cleaning it up when I have some free time. I'll post pictures when I make progress. Thanks for the advice!

If all else fails, would be a perfect host for shooting Speer primer powered plastic bullets out of.
Speer Plastic Bullets

I want something exactly like this to experiment with.

Same here.

not worth salvaging.  go buy a new one and use it for a paperweight... you could do all kinds of tests, and think it safe to shoot, the it could just let go and hurt you...

Bumping to see if OP ever attempted to restore or took pictures after cleaning.

Since we have a bump.

Rule of thumb, if the grips [or stock on a rifle] is burned then the fire was hot enough to damage the metal.

In my shop I get house fire guns to appraise for insurance companies at least once a year. So have seen quite a few over the years.

The weapon in the picture would be unsafe on all counts imo.

Does it differ with wood stocked guns vs plastic? I would think that a lot of rubber and plastic stocks

would burn or melt at much lower temps.

What is the criteria? What is the scientific basis for your conclusions?

A study on heat effects of metal?

Is there a book, with scales?

I'm curious on how you arrive at your conclusions.

If the springs are still good, it is worth trying to clean up.

It looks questionable, but you never know.

Provided the springs are OK, I admit that I might just shoot only .38 Specials in it.

It would be a shame to junk it though.

And, if restored to firing condition, it does eventually need to fire a few magnums.  Wouldn't be right to just shoot .38s in it, then have it sold as part of your estate, without the buyer knowing its history.

K-frames fired .38 Spls for decades with non-heat treated cylinders, barrels and frames.

I know people that have done this method before with good results.

http://www.frets.com/HomeShopTech/QuickTricks/RustRemoval/rustremoval.html

I bought this little plane at a garage sale, and it sure is orange with rust!



Thanks to the Internet, I've been reading about this cool way to eat rust using simple household gear.  All I have to do is mix up some baking soda in water in a plastic container, and connect the negative lead from my regular car battery charger to the rusty item and the positive lead to a piece of steel.  Immersing both items in the solution, making sure they don't actually touch, I simply turn on the juice, and bubbles come streaming off as the rust is eaten away:





I can retrieve the plane body in a few minutes after the rusty areas have all turned black:



And, after just a quick wipe with a towel, the rust is simply gone:



What a simple and effective technique!

My old Unisaw lives in a shed most of the year, and recently I noticed a bit of rust forming on the table surface:



Just for fun, I thought I'd try using the electrolytic technique on it.  I brought out my battery charger and mixed up my baking soda solution, dunked a small hand dowel in the liquid, and laid the wet towel over some of the rusty area:



Then, on top of the towel, I laid a steel sheet, making sure it didn't touch the table directly, and connected up my battery charger with the negative lead on the table, positive on the steel strip:



I used a nonmetallic weight to press the sheet down relatively flat:



Just as with the plane body, it made short work of the rust:



Those white spots are just little foamy areas of the electrolyte that formed as I lifted off the towel.

A quick wipe to clean the black gunk off:





And, would you look a that?  The rust was simply erased:

Yes there is an exact science to how heat effects metal, known as heat-treating, tempting or annealing.


A fire over 420f can start annealing (making it softer). Offhand I'm not sure of the calculations, but there is a time and temperature calculation that can estimate hardness of metals.

If I were to try and use the pistol, I would properly anneal and reharden the metal. However, doing that, or the fire itself may have changed the fitting tolerances on the parts.


A cool thing that could be done at home with a bunch of time, charcoal, a BBQ pit and a thermometer is color case hardening.

I'm well aware of metal heat treating techniques and the science behind it. My question is what criteria did he use to conclude that the pistol in the OP is damaged beyond repair and unsafe?

How did he determine this? How can he definitively determine what temperatures the pistol was exposed too? What tests can be performed, or signs are exhibited?

School me.

There are several methods.

One, and possibly the one mentioned here is years of experience seeing burned guns.  
After seeing enough, you develop the ability to tell if the gun hasn't been damaged, or is likely unsafe.  You can often tell if the damage is just burned wood that didn't affect the metal, or if the damage is nothing but water and smoke damage that didn't affect the metal at all other then appearance.

Another is to do Rockwell hardness tests.  Parts that are too hard or too soft indicate serious damage to the heat treating of the steel.
A good non-scientific rule of thumb is, if the springs are bad, or you see the metal has discolored, it's a safe bet the heat treating has been compromised.

In any case, a gun burned as badly as the one shown here is almost certainly not safe to shoot.
Short of having it inspected by a real metallurgist you can't be 100% sure, but it's sort of like playing Russian Roulette with three of the chambers loaded.
Cleaning up a gun like this and shooting it with ANY ammo is taking an insanely unsafe chance the gun will suddenly turn into a hand grenade in your hand while it goes off.
Life is short enough, and you only get two eyes, and five fingers per hand.

A real part of the danger is that a compromised gun may not blow up......immediately.  
It may fire a number of rounds before it goes, and that may not be until the gun has passed into unsuspecting hands.
We warn people never to fire old Damascus barrel shotguns, and that's for the excellent reason that they're known to be unsafe with modern ammo, and if compromised, may be unsafe with black powder.
Burned guns are in the same class.   It just isn't worth the very possible results.
Like Damascus barreled shotguns being used in spite of warnings, people just refuse to accept that a burned gun is just too risky.

Thanks for your explanation, your advice is held in high esteem by me.

I am curious, because  I have a lot of interest as a hobby gunsmith, I  like doing restoration work; I am currently working on a fire damaged Winchester 94 for a friend.

As a 23 year veteran Professional Firefighter, I don't see that pistol as having been exposed to heavy fire conditions. To me, it appears to have had burning debris fall on and bury it, at which point the grips burned. I would doubt it got very hot at all, and rubber grips burn at a relatively low temperature.I would like to see it cleaned up and what the internals were like. I would also be curious as to whether it was loaded, and what were the effects on the ammo.

Of course, that's a lot of assumption from a single photograph, and I might quickly change my opinion if I were able to handle it. If there is a technical procedure for determining the effects of heat exposure, I would like to learn what it is.

A technical procedure would require a professional metallurgist with a lab.
That would possibly involve destruction of part of the gun in testing.

This is why fire burned guns are so dangerous.  There's no simply do-it-yourself method of being sure it's safe or not safe, so too many people just figure it's good.

Sounds like a perfect wet leather holster mold.

Doesn't look all that bad to me, mostly seems covered with the various plastic garbage that trailers are made from.



See how it cleans up, and if the metal has significant discoloring, find someone to do a hardness test on it to confirm if it's fine.



Alternately sleeve the chambers and bore for .22 and enjoy your new .22 revolver!

Best option:

Lamp project