Why did so effective a .357 SIG become a thing of the past? .357 SIG Introduced in 1994 by SIG SAUER and Federal Premium Ammunitions, .357 SIG was presented with an evident engineering case: to have the speed of .357 Magnum in a duty-size semi-auto with no revolver cylinder. This was an odd formula of a round-of-service, one with no rim, with a bottleneck, to force a bullet of a weight equal to that of a 125-grain cartridge, with a hollow hollow barrel to work reliably, and to expel a bullet of a weight that might be called “magnum-like” by an autoloader apparatus.
The bottleneck shape is the signature of the caliber. It even describes a lot of its future destiny. The design requires the ammunition makers to shape and neck a (more complex) case than straight-wall pistol rounds, and it requires the shooters to accept a louder report, sharper blast and a training pace that some of the agencies eventually found to be more difficult to maintain at scale. A storytelling about the caliber was no longer about whether they worked but whether enough of the people could afford to keep it working: by a practice-qualified-steady-supply cycle. Once the general handgun market had driven into 9mm lines, the additional caliber in the logistics chain was a simple cull, even though the cartridge might never have ceased functioning.
During the late 1990s and early 2000s, law enforcement was the place where .357 SIG identified with the most. It provided faster velocities in duty pistols and gained a reputation of reliability in use with modern jacketed hollow points. As time went by that institutional footprint shrank. A user discussion of the current state has suggested that the Secret Service and Federal air marshals have gone away from using .357 SIG and back to using 9mm, attributing to a general trend toward heavier weight gravitation toward 9mm as bullet designs and training funds remained limited.
That was not the case since .357 SIG just ceased to be effective. Gel testing depicts how the cartridge has continued to present technical validity in the combination with modern projectiles. Of a series of nine loads tested through a Glock-pattern test platform, four of the nine loads showed average penetration in the FBI 12-18 inch range as well as provided repeatable high expansion and other loads hit within reach of serviceability on interpretation of synthetic-gel over-penetration pattern. The moral of the story is rather plain, yet significant: the cartridge still does its duty ammo kinds of things well.
The place where .357 SIG really disappeared was in the mid-tiers of the ecosystem-training ammo, shelf presence and the quantity of new pistols being sold out of the chambering. The unspun view of the concealed-carry community sums up the self-enriching nature of scarcity: “This lack of availability helps to break the price,” which prevents casual use, which again reduces availability. Once that cycle gets going even an otherwise technically powerful cartridge may become a niche product.
However, .357 SIG is not dying away since it has a different engineering niche. It wraps a speed in a service-size pistol; it does not use overly large bullet diameter; and it can be mounted on platforms that already were constructed to the dimensions of a .40 S&W pistol, with caliber conversion being possible by barrels and magazines, and not by full-scale replacement pistols. To amateurs and even to certain practitioners, it is still that combination, flat shooting of a handgun, solid terminal performance with the right ammunition, semi-autonomous capacity, that keeps the cartridge still in regular production, though it no longer commands the middle of the market.
