Dave T
Member
I have a good friend of over 30 years who is an engineering physicist. He has worked on projects that are currently in space and now works in what he jokingly refers to as "the military/industrial complex" (think missiles). His engineering skills are almost legendary in his speciality field.
Over the Christmas holidays we got together and I showed him the 5" pre-27 (made in 1954) I posted a picture of here. He admired it quite a bit and sent me the following engineering rundown on the weapons of that era. I thought his comments about Smith & Wesson would be of interest here.
"After seeing your S&W 357 I started thinking about the state of American manufacturing at the time the weapon was made. American metallurgy and quality of manufacture were nearly at their height in the 1950s. During the 1950s and to a lesser extent in the 1960s, American metallurgy produced a remarkable variety of high performance materials in both quality and quantity. Your new S&W is an example of this. Another example is the use of an advanced aluminum alloy, 75 ST (now known as 7075) in the frame of the Colt Commander. This was the first aluminum alloy with the yield strength of steel; unfortunately its fatigue properties later turned out to be inferior of those of steel. Incidentally, 75 ST was quite important in postwar aviation, enabling the development of high performance jets and very long range aircraft. The Stellite liner for the M60 machinegun barrel was developed about this time. With a Stellite lined barrel an M60 can fire the “basic load” of ammunition carried by an infantry unit without a barrel change, at least at normal rates of fire. Even when used in sustained fire, with a Stellite liner the barrel is changed after three to four times more rounds than with a comparable conventional barrel, from say for the German MG-34. Finally, the M-14 receiver used 8620H steel, and is perhaps at the very pinnacle of US firearms metallurgy. Proof of this is both the difficulty of manufacture; H&R in particular had great trouble making the receiver, and the incredible longevity of the receiver. It is claimed that the M-14 receiver service life is around 400,000 rounds or more; again the receiver service life of a contemporary weapon such as the FAL is around 60,000 rounds. Some advanced metallurgy did not get into the firearms world, which is unfortunate. The maraging steels offer incredible performance and are relatively easy to work, however these metals are not used anywhere in the firearms industry. By 1960 the range of tool steels available in the US was incredible; there was an alloy for almost any cutting application. In addition specialty alloys were common for certain applications. At this time designers could get industrial development of alloys for certain applications; today it is necessary to design to an ever shrinking list of alloys.
Your S&W 357 Magnum is made of a 41 series steel, probably 4130. This steel offers a good combination of high strength and toughness. The 41 series steels are still the best for firearms use; the M-16 barrel is made of 4150 (and there is a MIL-STD for this alloy for barrel use). The frame was made as a “closed die” forging to near net shape. A fairly elaborate heat treatment is necessary after forging to produce the optimum properties for the steel. Final machining was by broaching. Broaching is almost unknown today, but was common fifty years ago. The broach is a pyramid shaped cutting tool, which is oscillated along its long axis. The tool is slowly forced through the aperture in the frame to produce the rectangular aperture for the cylinder. S&W probably has more experience with broaching than any other company. Incidentally, the cost of broaching machine tools is one reason that revolvers are not common today. The combination of high quality steel, forging, heat treating, and broaching produces a very high performance product. Today S&W makes frames from free machining steels; it often uses type 416 stainless in its products. This type of stainless steel is easy to machine, and does not require heat treatment. However the properties of 416 are inferior to that of 41 series steels, as users of the Model 66 quickly learned! In the 1950s S&W could use forging shops that were located nearby; today the part must travel to the Midwest or elsewhere for this operation. Ruger uses investment casting to produce revolver frames; again the properties of an investment casting are inferior to those of a forging, no matter what the advocates of the process may say. (About a year ago I saw US Army mortar barrel forgings stacked up like logs at Scot Forge in Illinois; the Army did try an investment cast mortar barrel without success.)"
I got his permission to post this but he asked that his name and contact info be left out so I'm respecting his privacy.
Dave
Over the Christmas holidays we got together and I showed him the 5" pre-27 (made in 1954) I posted a picture of here. He admired it quite a bit and sent me the following engineering rundown on the weapons of that era. I thought his comments about Smith & Wesson would be of interest here.
"After seeing your S&W 357 I started thinking about the state of American manufacturing at the time the weapon was made. American metallurgy and quality of manufacture were nearly at their height in the 1950s. During the 1950s and to a lesser extent in the 1960s, American metallurgy produced a remarkable variety of high performance materials in both quality and quantity. Your new S&W is an example of this. Another example is the use of an advanced aluminum alloy, 75 ST (now known as 7075) in the frame of the Colt Commander. This was the first aluminum alloy with the yield strength of steel; unfortunately its fatigue properties later turned out to be inferior of those of steel. Incidentally, 75 ST was quite important in postwar aviation, enabling the development of high performance jets and very long range aircraft. The Stellite liner for the M60 machinegun barrel was developed about this time. With a Stellite lined barrel an M60 can fire the “basic load” of ammunition carried by an infantry unit without a barrel change, at least at normal rates of fire. Even when used in sustained fire, with a Stellite liner the barrel is changed after three to four times more rounds than with a comparable conventional barrel, from say for the German MG-34. Finally, the M-14 receiver used 8620H steel, and is perhaps at the very pinnacle of US firearms metallurgy. Proof of this is both the difficulty of manufacture; H&R in particular had great trouble making the receiver, and the incredible longevity of the receiver. It is claimed that the M-14 receiver service life is around 400,000 rounds or more; again the receiver service life of a contemporary weapon such as the FAL is around 60,000 rounds. Some advanced metallurgy did not get into the firearms world, which is unfortunate. The maraging steels offer incredible performance and are relatively easy to work, however these metals are not used anywhere in the firearms industry. By 1960 the range of tool steels available in the US was incredible; there was an alloy for almost any cutting application. In addition specialty alloys were common for certain applications. At this time designers could get industrial development of alloys for certain applications; today it is necessary to design to an ever shrinking list of alloys.
Your S&W 357 Magnum is made of a 41 series steel, probably 4130. This steel offers a good combination of high strength and toughness. The 41 series steels are still the best for firearms use; the M-16 barrel is made of 4150 (and there is a MIL-STD for this alloy for barrel use). The frame was made as a “closed die” forging to near net shape. A fairly elaborate heat treatment is necessary after forging to produce the optimum properties for the steel. Final machining was by broaching. Broaching is almost unknown today, but was common fifty years ago. The broach is a pyramid shaped cutting tool, which is oscillated along its long axis. The tool is slowly forced through the aperture in the frame to produce the rectangular aperture for the cylinder. S&W probably has more experience with broaching than any other company. Incidentally, the cost of broaching machine tools is one reason that revolvers are not common today. The combination of high quality steel, forging, heat treating, and broaching produces a very high performance product. Today S&W makes frames from free machining steels; it often uses type 416 stainless in its products. This type of stainless steel is easy to machine, and does not require heat treatment. However the properties of 416 are inferior to that of 41 series steels, as users of the Model 66 quickly learned! In the 1950s S&W could use forging shops that were located nearby; today the part must travel to the Midwest or elsewhere for this operation. Ruger uses investment casting to produce revolver frames; again the properties of an investment casting are inferior to those of a forging, no matter what the advocates of the process may say. (About a year ago I saw US Army mortar barrel forgings stacked up like logs at Scot Forge in Illinois; the Army did try an investment cast mortar barrel without success.)"
I got his permission to post this but he asked that his name and contact info be left out so I'm respecting his privacy.
Dave
