It had a full-length grip that accommodated an 8-shot magazine, a 4" barrel, and a hammer-dropping safety. In the early Eighties production shifted to the Second Generation versions of the same pistol. These came in three flavors: the Model 439 with an aluminum frame and carbon steel slide, the Model 539 with a carbon steel frame and slide, and the Model 639 with a stainless steel frame and slide. These were still full-size pistols with 4" barrels and 8-shot single-stack magazines.
The earliest single-stack Third Generation autos introduced in 1988 were very similar: The 3904 with a carbon steel slide and alloy frame, and the 3906 with a stainless steel frame and slide.
Soon, however, came a Third Generation single-stack nine that was different than earlier models...
The Seventies and Eighties had seen several custom "chopped" subcompact versions of the Smith single-stack nines, the ASP and Devel.
These went for hundreds of dollars for the custom work, with that price being added on top of the base gun. Reliability could sometimes...well, let's just say it could require a little "tweaking" before things settled out.
Then Smith & Wesson launched their own in-house Model 3913 in 1989. With a barrel chopped to three and a half inches, a shortened grip that still retained an eight-shot magazine, and a no-snag bobbed hammer from the factory, the 3913 was a factory subcompact 9mm that was years ahead of the Kahr or Glock 26. It was utterly reliable, weighed 25 ounces empty, and its MSRP of six-hundred and twenty-two bucks was barely more than what a custom house would have charged to chop a customer-provided 3904 into a compact carry blaster.
It wasn't long after the 3913 was released that the full-sized 3904 and 3906 were discontinued. Apparently someone at Smith & Wesson thought that the future for full-size pistols was in double-stack duty guns, and single-stacks should be compacts.
The pictured pistol shipped from the factory with Novak lo-mount night sights and no magazine disconnect, likely indicating that it was ordered by a police department as a duty or backup gun. It was acquired from a local gun store in 2021 for four and a half bills.
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