Smith & Wesson K Frame Model 12 Airweight Bolt Spring & Plunger Old Style .38 Special — Used OEM Part 1245A

Smith & Wesson K Frame Model 12 Airweight Bolt Spring & Plunger Old Style .38 Special — Used OEM Part

Genuine Smith & Wesson OEM bolt spring and plunger for the K Frame Model 12 Airweight revolver chambered in .38 Special. The bolt spring drives the bolt (cylinder stop) upward into the cylinder notches to lock the cylinder in alignment with the barrel at each chamber position. The plunger transmits the spring force to the bolt. A weak, broken, or missing bolt spring causes the cylinder to fail to lock up properly, resulting in misalignment between the chamber and barrel — a safety-critical condition. This is the old-style spring and plunger set specific to the Model 12. This used OEM set is inspected and functional, manufactured to original S&W specifications and tolerances.

Condition: Used — inspected and functional. Some fitting by a qualified gunsmith may be necessary.

Specifications

• Part Number: 1245A
• Manufacturer: Smith & Wesson
• Part Type: Bolt Spring & Plunger
• Frame: K Frame
• Compatible Model: Model 12 Airweight
• Caliber: .38 Special
• Style: Old Style
• Condition: Used — genuine OEM part, inspected and functional

Compatibility

Note: This is the old-style bolt spring and plunger. Verify your model and part style before ordering.

Finding Your Model Number

Swing out the cylinder and look behind the yoke on the frame. Model numbers were added starting in 1957–58. If your revolver has no model number stamped, it may be a pre-model variant — contact us with your serial number for assistance.

Important Notes

• This listing is for the bolt spring and plunger only. The bolt and all other action parts are sold separately.
• Used condition — some fitting by a qualified gunsmith may be necessary.
• Action disassembly is required for installation. Gunsmith installation recommended.
• Always function test after installation to confirm proper cylinder lockup and timing before firing.