SIG-Chylewski Single-Hand Pistol

A Fascinating Chapter in Firearm History

The SIG-Chylewski single-hand pistol stands as a unique piece of firearm innovation, blending ingenuity with the challenges of early 20th-century weapon design. Its creator, Witold Chylewski, a Polish engineer based in Vienna, entered into an agreement with SIG in Neuhausen in 1919. Under the terms, SIG would produce 1,000 units of Chylewski’s innovative pistol, with the option for global sales rights (excluding North and South America) if the design gained traction.

Despite its promise, the pistol quickly revealed a critical flaw—it was prone to accidental discharges under improper handling. In response, SIG retrofitted most of the pistols into conventional configurations, eliminating the risk. This rework effectively transformed the Chylewski pistol into a more traditional firearm while preserving its mechanical integrity and reliability.

SIG adhered to the original production cap of 1,000 units, all chambered in 6.35mm caliber. Intriguingly, SIG also explored a 7.65mm variant, though it only reached the prototype stage, leaving collectors today with tantalizing glimpses of what might have been.

Two main versions of the 6.35mm Chylewski pistol exist:

Original Configuration:

The left side was engraved with: SOCIÉTÉ INDUSTRIELLE SUISSE NEU-HAUSEN.
The guide rail of the first trigger guard is marked with Brevet CHYLEWSKI.
The weapon serial number is engraved on the grip frame above the rear trigger guard.

Modified Version:

The front trigger was locked via a lateral screw and recessed.
The lower guide rail was shortened and fine-tuned.
Slide inscriptions were milled down, leaving only Brevet Chylewski on the guide plate alongside the serial number on the grip.

The Chylewski single-hand pistol was an ambitious but ultimately flawed endeavor. Its short production run and subsequent modifications make it a rare and intriguing piece for collectors. After this project, SIG shifted focus and, two decades later, adopted the design of the French Petter Model 1935 A in 7.65mm Long, marking the beginning of a new era in SIG’s storied history.

For enthusiasts and historians, the C+3hylewski pistol is more than just a firearm—it’s a testament to the trial-and-error process of firearm innovation during a transformative period in weapon design.

The Specs and information on the different gun models listed below are based on Das Grosse Buch der SIG-Pistolen, “The Big Book of SIG Pistols,” by Lorenz Vetter.