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S&W J Frame Thumb Piece & Nut New Style .357 Mag Used, Part 340181A

$24.99

Factory OEM Smith & Wesson thumb piece and retaining nut assembly for J Frame centerfire revolvers, new-style design. Used surplus part in good working condition.

Specifications

  • Part Number: 340181A
  • Includes: Thumb piece and retaining nut
  • Style: New Style
  • Caliber: .357 Magnum / .38 Special (centerfire)
  • Frame Size: J Frame
  • Condition: Used / Surplus
  • Brand: Smith & Wesson

Function

The thumb piece (cylinder release latch) allows the shooter to swing the cylinder out of the frame for loading and unloading. The retaining nut secures the thumb piece to the frame. A worn, bent, or missing thumb piece will prevent cylinder release and render the revolver inoperable. Replace with this factory assembly to restore proper cylinder release function.

Compatibility

Model Caliber Frame Notes
Model 340 .357 Mag / .38 Spl J Frame New style — verify before ordering
Model 340PD .357 Mag / .38 Spl J Frame AirLite Sc — New style
Model 360 .357 Mag / .38 Spl J Frame New style — verify before ordering
Model 360PD .357 Mag / .38 Spl J Frame New style — verify before ordering
Model 640 .357 Mag / .38 Spl J Frame New style — verify before ordering
Model 649 .357 Mag / .38 Spl J Frame New style — verify before ordering

Important: This is a new-style thumb piece. Verify your revolver uses the new-style design before ordering — old and new style thumb pieces are not interchangeable. Rimfire J Frame models (43, 63, 317) are not compatible.

Installation Note

Professional installation by a qualified gunsmith is recommended. Verify smooth cylinder release and positive lockup before returning to service.

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