Where is the strength located?

[mete]

Few remember but Hammerli made at one time SA revolvers ! They looked at ALL things .For example as the bullet enters the barrel it has to do two things ; line up with the barrel axis , and engage the rifling. They found it better for accuracy to separate the two. First a groove diameter section to line up the bullet , then a rifled section ! More accurate !
The resistance to swaging the bullet into the rifling causes a pressure rise .
Another factor is the hot gas which can , depending on the powder and pressure, cut into the top strap. For some of the new aluminum or titanium light weight revolvers , read and follow instructions ! Powder , bullet weight and cleaning procedures can damage the special coatings on the metal If not followed !
A good engineer considers all factors !

 

[mete]

Sequins , those old photos are great !! I've used belt driven machines .The photos are a machinists dream ! But they don't go back far enough. All along places like the CT river they had factories --ALL water powered !! I think there are some museum factories still powered that way !

 

[Driftwood Johnson]

All along places like the CT river they had factories --ALL water powered !! I think there are some museum factories still powered that way !

A little bit off topic, but once steam power became practical, it pretty much supplanted water power for factories. Water powered mills were dependent on river flow. Water power was dependent on the head of water. You could not milk any more power out of a river than existed at the head. And during the summer months, when flow was down, water powered factories could not produce at peak power.

Steam power did away with these problems. Not dependent on weather, or gravity. As a mill grew, if more power was needed, it was easy enough to add another steam engine. And all you needed was more coal, you were not dependent on how much rainfall there was in the summer.

The steam engine in the photos I posted is very typical of the type of power that powered the mills here in New England once the mills started becoming large. S&W had a Corliss engine right into the 1930s. The mills in Lowell, the heart of the industrial revolution in America, became steam powered mid way through the 19th Century. Look at any photo of a large mill or factory during the late 19th century and you will see a tall smoke stack. That was there for the boilers that powered the steam engines.

This is the stack behind the mill. It is no longer in use, now there are cell phone antennas on top.

Another view of the old smokestack. The steam engine is behind the glass doors to the left. In the old days, there was a boiler room between the smokestack and the mill, where steam was generated for the steam engines. The boiler room is gone now.

This old pen and ink drawing of the Colt factory in the 19th Century shows the smokestack. The river boat and the factory are both powered by the same means, coal heating water to generate steam.

 

[tipoc]

If you have a .38Spl revolver and a .357 revolver you have a gun with the same bore. Same with .44Spl and .44Mag.

Yet each gun in the mag category will handle far higher pressures than the Spl.

Why?

Where is the strength located in the gun. With a .38Spl and a like-sized .357Mag side by side which components will be the more heavily engineered?

My guess is the cylinder. But what about the barrel?

When S&W first introduced the .357 magnum they specially heat treated the cylinder to provide more strength, they also experimented with new steel alloys before doing so. They also strengthened the yoke. and for the first time heat treated some of the internal parts they expected to be battered more than their N Frame 38s had shown. They also used a new steel alloy for the barrel that was better able to withstand the increased velocity and increased pressures with less wear than the steel they had used in previous barrels.

No one had ever built a revolver that operated at the pressures that the .357 Magnum operated. S&W took great care. When they were looking for Winchester to help them make the new load and new cartridge, Winchester refused saying that it would be irresponsible to do so and dangerous. Remington said yes.

Over the decades the 357 magnum revolvers went through many improvements a number for strengthening the internals of the gun. You can trace these in Supica and Nahas' "Standard Catalog of Smith and Wesson", now in it's 4th edition (is the 5th coming?).

When S&W introduced the K frame Combat Magnum (which became the Model 19) in the 1950s it strengthened the cylinder for handling the .357 Magnum rounds and beefed up the yoke, over it's K frame cousins chambered in lesser rounds. Over the years other changes took place in the K frame .357s strength and durability, till supplanted by the L frame. Oh and the M19 always had a heavy ribbed barrel, never the pencil barrel.

The same is true for the 44 Magnum over the years. Again Supica and Nahas will help.

The strength of the cylinder is key. So is the durability of the smaller parts of the gun that take a battering under recoil and the frame. S&W found that had to heat treat the frame as well.

Phil Sharpe in his book "Complete Guide to Handloading" devotes a couple of chapters to the development of the .357 Magnum and it's loads. He was instrumental in it's development. He dispels some myths.

Timothy Mullins book on the .357 Magnum is also helpful.

tipoc

 

[Bob Wright]

James K:

The barrel, of course is a pressure vessel; if not, why not make barrels of aluminum or plastic?

They do just that now, of aluminum alloy, anyway. They are lined with a steel liner for wear.

Bob Wright

 

[Jim Watson]

Plastic, too, they just call it "carbon fiber composite."