Verified answer

The traditional material for revolvers and pistols is and has always been carbon steel with either a rust blue or nickle-plated finish.

Starting in the mid-1960's revolver makers began experimenting with stainless steel for revolvers. To the best of my knowledge, now one was successful in making a stainless steel pistol until the early 1980's. The reason is that existing stainless steel alloys had a serious problem with the slide and frame galling each other. I can't remember the name of the alloy that finally beat this problem.

The traditional lightweight frames were made of an aluminum alloy, and were generally said to be "alloy frames." Where a steel frame Model 40 Centennial Revolver weighs 21 ounces, an alloy framed version, the Model 442 weighs a mere 15 ounces.

In the last few years several of the big manufacturers have been afflicted with a craze to make the lightest possible revolvers in the most bloody inappropriate calibers. Titanium and Scandium are the newest alloys. I'm not sure about the scandium revolvers, but the titanium revolvers must have a steel barrel insert because the titanium won't hold rifling, and the scandium framed models require stainless steel cylinders to contain high pressures.. As an example of the lack of weight, compare the Model 629, a stainless steel large (N) frame .44 RemMag revolver which weighs 41.5 ounces with a 4" barrel, while a 2.5" Model 329, a large (N) framed scandium framed .44 RemMag weighs only 29.5 ounces. In the small J-frame revolvers the weight difference is even more marked. A Model 640 Centennial in .357 magnum weighs 23 ounces, the same revolver with a scandium/titanium frame, the Model 340, weights a mere 12 ounces. Recoil from these mosquito weight revolvers is horrendous. The worst thing about them is that many novice handgunners are buying them because they are so light and easy to carry. They don't realize that without a tremendous amount of practice, their new revolvers will be virtually uncontrollable.

Semi-automatic pistols are available in the same carbon steel, stainless steel and aluminum alloy materials as revolvers. In addition there are a number of pistols on the market that use any one of several different polymers as frame material. Remember the great whooraw about "plastic pistols" being invisible to metal detectors? That was so much horse manure! While the frames are made of polymer, the barrels, slides, springs, slide stops, and magazine bodies are made of steel and even the frame is readily identifiable as a firearm even by the stupidest airport rent-a-cop.

Doc

njmotorc is correct. I don't think you could get much better an answer.

I would like to add that the difference between a quality 1911, of 40 years ago, and the same model today, giving its the same metal, is its manufacturing process.

With the advent of more precise CNC machining, it is possible to make tools like a 1911 pistol to exacting tolerances.

Also when you lighten the weight of some of the magnum calibers such as a .357, or a .44mag, the bullets, should they be shooting a light grain weight hot load, the remaining rounds will "jump crimp". This is to say that when a super light scandium Smith and Wesson snub fires a full power 110 or 125 grain mag, the remaining bullets can actually come out of the case a bit because the gun comes back so fast and long. If the bullets come out of their case too much, you will stop the rotation of the drum, rendering the weapon about as usefull as a paperweight. You will notice that on many snub magnums, they specify a minimum grain weight to avoid this problem.

Scandium, titanium, polymer all have a place in the firearm world, but each has a cost for the weight they save.

I like njmotorc am a police officer(stay safe brother), and have been carrying a steel sig on and off duty for years. My agency recently went to a polymer fram Smith, and I am not fond of it. It has some benifits, but not to the point to switch from a Sig.

Stick to a steel frame gun of good quality, and you should be able to shoot it for a few lifetimes.

As far as revolvers go, steel is the original and still the best. Its the strongest and longest lasting.

Aluminum was used as a weight saving alternative. The lighter weight made the gun easier to carry but also increased felt recoil significantly and didn't last nearly as long (number of rounds, not number of years) as a steel frame would. Aluminum frame revolvers still use conventional steel cylinders and barrels.

Scandium and titanium are the same as aluminum, attempts to reduce weight at the cost of longevity and felt recoil. Most use some type of steel insert instead of the entire barrel and cylinder being steel.

As with revolvers, all autos were originally steel. Again, steel is still the best for strength and longevity (assuming good quality steel is used).

Also as with revolvers, aluminum frames were used to reduce weight but the slide, breech block, and barrel were still made of steel. Felt recoil didn't increase as much as with revolvers because the frame is a smaller percentage of overall mass on autos. Again, the aluminum frames won't last as long as the steel frames.

Polymer frames were introduced as a lighter weight alternative and as an item that was much easier to manufacture. As you point out, they don't get too hot or too cold but, like aluminum, they don't last as long as a steel frame. Lack of corrosion is also a big selling point for those who carry them next to thier skin or who live in humid or wet environments. There have been many problems with polymer frames cracking from the repeated impacts of the slide going back and forth. This has happenned with several manufacturers, most recently with Kahr.

When Gaston Glock invented the polymer frame he reasoned (correctly) that most guns aren't fired all that much so the trade-off of longevity for the easier manufacturing (and lower cost to the consumer) was a good deal. There is at least one company that manufactures steel, aluminum, and titanium frames for Glock pistols.

With the exception of my police issue Sig, all of my guns (autos and revolvers) have steel frames and they always will.