The 357 Magnum Cartridge

History and Development of the 357 Smith & Wesson Magnum

357 Magnum Gun and Ammo

Smith & Wesson Model 66 357 magnum revolver with ammunition. S&W made the first guns available for this round, and have probably made more than anyone else. Photo © Russ Chastain

The 357 magnum handgun cartridge has been around for many decades (it was introduced in 1935), and it’s showing no signs of losing popularity even as its eightieth birthday looms. This cartridge eclipsed its predecessor, the 38 S&W Special, even though it was just a little bit longer. Originally known as the 357 Smith & Wesson Magnum, its name is usually shortened to “357 S&W Magnum” or “357 Magnum” for the sake of brevity.

The pages of shooting history are littered with cartridges that tried and failed. Only a small percentage of them have the right recipe — a combination of practicality, performance, and appeal — that lets them keep on keepin’ on. The 357 magnum is one of those few.

Development

Development of the 357 magnum was a joint venture between Smith & Wesson (S&W), which provided the platform in the form of a large-frame revolver, and Winchester, which provided the ammunition. Major Douglas B. Wesson of S&W and Philip B. Sharpe of Winchester performed most of the development work.

In the 1930s, the revolver was the most popular type of handgun. Semi-automatic pistols had been around for a good while, but a combination of high price and low reliability prevented their popularity from really swelling. During this time, the old faithful 38 Special had grown to become one of the most popular revolver  cartridges around, but for many applications it was woefully underpowered.

Shooters toyed with loading more powerful 38 Special ammunition, but the problem was with the guns; while newer firearms built on strong frames could handle more powerful loads, many older 38 Special revolvers couldn’t. As always, commercial ammunition manufacturers used the weakest guns to determine the maximum pressure to which they would load the 38 Special, and for a time the 38 languished — still popular, but lacking steam after three decades of marginal improvement. Something new was needed.

The First American Magnum

The idea was to create a new cartridge that used a similar cartridge case, but which couldn’t be chambered in older, weaker revolvers. This would ensure that all factory guns chambered for the 357 magnum would be strong enough to handle its increased chamber pressure (35,000 PSI vs. 17,000 PSI). The developers kept things basic, and simply lengthened the cartridge case by about one-tenth of an inch. This prescient move meant that a 357 Magnum revolver could also fire 38 Special ammo.

The name was created by using the actual bullet diameter of a 38 Special bullet (.357 inch) and adding the word “magnum,” which had already been established as meaning “powerful” in the ammunition world. The 357 Smith & Wesson Magnum was the first American magnum cartridge, and naturally made a splash among shooters as a result.

With more than three times as much energy and almost double the velocity of the 38 Special with 158-grain bullets, the 357 breathed new life into revolver sales and into handgun shooting. Because the new 357 had been developed by simply lengthening an already-popular straight-walled cartridge, it simplified manufacture of ammunition and guns and kept the 38 Special in vogue as well, because the older 38 Special cartridge works just fine in 357 Magnum revolvers.

The 357 S&W Magnum has been used successfully by experienced marksmen for hunting, although its range of power makes it a poor choice for large game yet too powerful for small game. There are definitely better hunting cartridges out there, and I don’t recommend hunting with the 357 Magnum. A 357 Magnum revolver is a good choice for self-defense, and its ability to safely fire 38 S&W and 38 Special ammunition makes it very flexible and easily shootable by both weak and strong shooters.

Rifles, revolvers, and even semi-automatic pistols have been produced to shoot this round, but the double action revolver remains the most practical and popular type of 357 gun.

Still Popular

The 357 Smith & Wesson Magnum enjoyed two decades as the world’s most powerful handgun cartridge before it was supplanted in 1955 by the 44 Remington Magnum, which is much better for hunting but generally more powerful than necessary for police work and self-defense. The 357′s popularity remains, and as I write this almost 60 years after it was knocked off its perch at the top of the heap, the first American magnum shows no sign of slowing down anytime soon.

Related

A lifelong hunter and shooter, Russ Chastain has made it a point to learn much about hunting, shooting, guns, ammunition, gunsmithing, reloading, and bullet casting. Having started toting his own gun in the woods at… [Learn More]


I want more stuff like this!

Sign up for the All Outdoor weekly email and never miss our most popular stories.