9x23 mm & .357 Sig

by
posted on October 31, 2013
** When you buy products through the links on our site, we may earn a commission that supports NRA's mission to protect, preserve and defend the Second Amendment. **
9x23mmWinchester_f.jpg

I watched Sheriff Jim Wilson fire the first round of 9x23 mm JHP ammo into a defenseless block of ordnance gelatin. It was at a writer’s seminar where the gun and cartridge were introduced to the shooting world. Jim may also have been present when another maker brought out its version of ammo for the .357 Sig cartridge. I can’t recall what the good sheriff had to say about these two rounds, but I’ll bet that he has observed the same thing that I have-one made it, one didn’t.

Both calibers were intended to bump up the ballistic performance level of mid-bore pistol cartridges. The 9x23 mm was a .45 ACP-length round intended for single-column M1911-style pistols. Approximately the same length as the .38 Super, the 9x23 was essentially a lengthened 9 mm Luger cartridge. Actually, it had another characteristic that was new to auto pistol design. In order to better handle the higher pressure that would make this so-called “long nine” perform, the case head was deliberately thickened. This gave the base of this cartridge greater mass and strength. It was an approach once tried in Jeff Cooper’s early SWPL days. Initial offerings in 1996 were Colt 1911 pistols, which fired the round with accuracy and power. Colt and Winchester Ammunition wanted a gun for the IPSC circuit.

In 1994, SIG collaborated with Federal to develop the .357 Sig cartridge. This redoubtable Swiss-German-American firm wanted a powerful medium-bore automatic pistol round that was short enough to comfortably fit in the double-wide magazines of.40 S&W-sized autos. They weren’t going after the gamesmen, but rather the warriors. Working from the already successful .40 S&W case, they necked it down to take 9 mm (not .357 inch) bullets of medium weight. It was a resounding success, achieving velocities in the mid 1,300 fps range. The forgoing description admittedly oversimplifies the cartridge development just a bit. The .357 Sig cartridge works in 9 mm-size pistols, where the bottlenecked case spells ultra-reliable feeding. The cartridge simply works.

Comparing the two is something of an apples-and-oranges thing in the sense that they were really intended for different roles. Whatever the intent, the fact is the 9x23 flopped and is now almost forgotten. And while it is used by a number of prestigious police agencies, the .357 Sig does not enjoy the wide success its designer/developers were seeking.

Latest

Gotw Tristar Arms Kr22 1
Gotw Tristar Arms Kr22 1

Gun of the Week: TriStar Arms KR.22

Semi-automatic .22 rifles have been a staple in the firearm marketplace for decades, and the TriStar Arms KR.22 brings yet another lightweight, affordable option that accepts Ruger 10/22 rotary magazines.

Political Report | Trump Reiterates National Right-to-Carry Support

I am repeatedly reminded of how critical it was that the NRA engaged early in supporting Donald Trump’s 2016 candidacy—and that he won. A recent example came in June, when President Trump spoke to American workers at a Mack Trucks facility in Macungie, Pa.

The Armed Citizen® Aug. 21, 2026

Read today's "The Armed Citizen" entry for real stories of law-abiding citizens, past and present, who used their firearms to save lives.

The Norinco TU-33/40: A Rimfire Mauser Lookalike from China

The Norinco TU-33/40 is, at a glance, a copy of a Mauser 98k with a few choice details that give away the fact that it’s not a big-bore World War II workhorse.

AI Tools Enter the Used-Gun Market

Companies that deal in the used-gun market are not shy about sharing the advantages their AI-driven tools and services.

Standing Guard | Standing on the Line for Freedom

This past August marks 46 years since I raised my right hand and was commissioned as an infantry officer in the United States Marine Corps. In the summer of 1980, I entered active duty with a firm sense of civic duty and a deep desire to serve our great nation. Like so many who wear the uniform, I was ready to contribute directly to the defense of freedom.

Interests



Get the best of American Rifleman delivered to your inbox.