.357 Magnum

.357 Magnum ammunition. On the left is JSP (soft point) round, on the right is JHP (hollow point).

".357" redirects here. For other uses, see .357 (disambiguation).

The .357 Magnum revolver cartridge was created by Elmer Keith, Phillip Sharpe and the firearms manufacturer Smith & Wesson. Based upon their earlier .38 Special revolver cartridge, the .357 Magnum cartridge was introduced in 1934 and its use has since become widespread.

Design

The .357 Magnum was developed over a period of time in the early to mid-1930's in a direct response to Colt's .38 Super Automatic. At the time the .38 Super Automatic was the only revolver caliber capable of defeating automobile cover and the early "Bullet Proof Vests" that were just then beginning to emerge in the Post World War 1 "Gangster Era". Tests at the time revealed that those early vests defeated any handgun cartidge travelling at less than ~1000 FPS. Colt's .38 Super Automatic just edged over that velocity and was able to penetrate car doors and vests that bootleggers, and "gangsters" were employing as cover.

To settle the score, and reassert itself as the leading Law Enforcement armament provider, Smith and Wesson developed the .357 Magnum. The new round was developed out of their existing .38 Special round, by adding additional powder, and ultimately by extending the case by 1/8th of an inch. The case extention was more a matter of safety than of necessity. Since the .38 Special and the new .357 Magnum cartridges were identical in physical attributes, it was possible to load a .357 Magnum cartidge in a .38 Special revolver, with potentially disastrous results. Extending the case slightly made it impossible to accidentally chamber the magnum power round in the smaller gun.

Much credit for the .357's development is given to hunter and experimenter, Elmer Keith. Keith's work in loading the .38 Special to higher and higher pressure levels was made possible by the availability of heavy, target shooting-oriented revolvers like the Smith & Wesson 38/44 "Heavy Duty" and "Outdoorsman", .38-caliber revolvers built on .44-caliber frames. While the .38 Special cartridge is limited to 16,500 c.u.p. (copper units of pressure), the .357 Magnum is loaded to 35,000 c.u.p. The objective was to create a handgun cartridge that combined deep penetration, flat trajectory, and long range. To prevent its possibly disastrous use in older, weaker .38 revolvers, the .357 Magnum case is 0.135 inches longer than the .38 Special case.

This cartridge is an excellent self-defense round; it still enjoys a reputation of being the gold standard of stopping power among handgun cartridges. Some of those who have used it have described a "struck by lightning" reaction in those hit with it. For big game, such as ungulates and bears (which have a sturdier build than humans), it is inferior to the .44 Magnum, .454 Casull, .41 Magnum and other bigger magnum rounds. Still, it is a fine small and medium game round and will kill deer very reliably at short range if used by a good shot. It has much more stopping power on game than the .45 Long Colt and the much flatter trajectory makes hits on small game much easier out to about 75 yards. It is a very versatile cartridge and can be used with success for self defense, plinking, hunting, or target shooting. .357 guns have the advantage of being able to use .38 Special ammo as well (with its lower cost, recoil, noise, muzzle flash, and, often, better accuracy), further extending their utility. It has also become popular as a "dual use" cartridge in short, light rifles, like the Old West lever-actions, and in a rifle the bullet will exit the barrel at about 1800 feet per second, making it far more versatile than the .30 Carbine or the 32-20 Winchester. In the 1930s it was found to be very effective on steel body armor, and metal-penetrating rounds were once popular in the United States among highway patrol and other police organizations. The .357 revolver has been largely replaced by modern, high-capacity semi-automatic pistols for police use, but is still very popular among outdoorsmen, security guards and other civilians. The .357 Magnum was a direct competitor with the .38 Super which was designed for semi-automatic pistols. The .38 Super can still give the .357 serious competition in barrels of equal length, but the .357 is more powerful especially as revolvers can have a long barrel that would be too clumsy for semi-auto designs.

In terms of accuracy, the .357 magnum has at least the same potential for precision shooting as the benchmark .38 special wadcutter round—indeed, a good .357 revolver will happily shoot .38 wadcutter ammunition and return good results. With tailored loads in a clean, sound revolver, wadcutter or semi-wadcutter target rounds (lead bullet, small charge of fast burning powder) will return groups of as little as 2 inches from edge to edge at a range of 20 yards with very little noise or recoil. Full power loads with good jacketed bullets and a heavy charge of a much slower burning powder can aspire to 2 1/2 inch groups with no great difficulty. It is this great versatility that makes a .357 revolver an excellent gun for many different disciplines, from 20 yard precision shooting to long range falling plate events. Being economical and consistently performing well in all but the strangest of load configurations, it is an excellent place to start if one should consider handloading.

The .357 Magnum started the Magnum era of high velocity handgun ammunition.

The .357 Maximum which was introduced in 1983 was based upon the .357 Magnum [1].

Performance

• Winchester 125 gr (8.1 g) Jacketed HP = 1450 ft/s (440 m/s), 583 ft·lbf (790 J)
• Winchester 158 gr (10.2 g) Jacketed HP = 1235 ft/s (375 m/s), 535 ft·lbf (725 J)

Synonyms

• .357
• .357 mag
• .357 S&W Magnum
• .357 Mangle'em (slang)
• 9x33mmR (European Designation)

See also

• .38 Special
• 9 mm Luger Parabellum
• .44 Magnum
• 357 SIG
• List of firearms
• List of handgun cartridges
• List of rifle cartridges

External links

• Coonan pistol - semiautomatic .357 magnum handgun