Ordnance Notes -- by Bob Stoner GMCM (SW) Ret.

S&W Model 39 9mm Automatic Pistol


The Smith and Wesson Model 39 was the first U.S. designed double action (DA) semi-automatic pistol marketed in the United States. The German Walther P38 DA pistol impressed American ordnance personnel during World War 2. The Army Ordnance Corps issued a proposal for an American equivalent to the P38. In 1949, Smith and Wesson began development of the Model 39 DA semi-auto in caliber 9x19mm Luger. Smith and Wesson began selling the Model 39 commercially in 1955. The Model 39 is considered a first generation pistol. Since the Model 39 came out, S&W has continuously developed the design into its third generation pistols that are now on the market.

The Model 39 uses a conventional slide, barrel bushing, and slide arrangement as opposed to the exposed barrel arrangement of the P38. Model 39 locking is done by a modification of the Browning P35 (High Power) cam-locked breech. First generation Model 39 slides used either a long, spring steel extractor or a spring-loaded, pivoting claw extractor. The long extractors tended to be fragile and were replaced by the pivoting type. However, the long extractor would extract ANY kind of 9mm Luger round (domestic or foreign) and the pivoting type was picky.

The Model 39 employs a decocking safety that disconnects the trigger and hammer similar to the P38. The Model 39 uses a single-stack magazine like the P38 (actually, S&W copied the German magazine and added a magazine catch cutout.) The Model 39 (like the P38) carries 8 rounds in its magazine, plus 1 in the chamber, for a maximum of 9. The overall length of the Model 39 is 7.6 inches, the barrel is 4 inches long, and its weight is 1.72 pounds. Light weight is a characteristic of the Model 39 due to its aluminum frame and a steel slide and

Photo of a post-WW2 version of the P38 made by Walther for the German Bundeswehr as the Pistole 1 (or P1). The principal difference between WW2 and post-war pistols was the frame: the P38 was steel and the P1 was aluminum. Parts were not always interchangeable because post-war guns had to be reverse-engineered from wartime guns. Shown in the photo are the pistol, a spare magazine, the cleaning kit, a holster, and the shipping box. Aside from an exposed barrel and external cosmetics, the characteristics of the P38 or P1 are very similar to the Model 39. (Photo: Impact Guns)

barrel (a characteristic shared with the post-war version of the P38, the German Walther P1).

The Model 39 was used by Naval Special Warfare units during the Viet Nam War. The Model 39 was issued to officers-in-charge (OICs) of MST-2 detachments as their sidearm. SEAL Teams used either the Model 39 without modification or a modified version, the Mk 22 Mod 0, also called the "hush puppy." The Mk 22 Mod 0 was modified pistol that had a silencer or sounds suppressor with a slide lock. Its purpose was to eliminate sentry dogs or guards without alarming the main target.

In service, the Model 39 was adequate but not reliable when exposed to mud and dirt. It was never in the same league as the M1911-series .45 or Browning P35 9mm. The Model 39 is obsolete in Naval Special Warfare units.

© 2005 Bob Stoner R3