S&W J Frame Model 642-2 Airweight Mainspring Stirrup & Swivel .38 Special +P – Part# 642K

Smith & Wesson J Frame Model 642-2 Airweight Mainspring Stirrup & Swivel – Stainless Steel

Restore reliable hammer fall and trigger pull on your Model 642-2 Airweight with this factory-original mainspring stirrup and swivel set. The mainspring stirrup is the U-shaped yoke that connects the mainspring to the hammer, transferring spring energy into hammer movement — the swivel allows the stirrup to pivot smoothly as the hammer travels through its arc. A worn, cracked, or broken stirrup or swivel causes inconsistent hammer fall, light strikes, or complete failure to fire. This stainless steel matched set is the correct factory replacement for the J Frame Model 642-2 chambered in .38 S&W Special +P.

• Part Number: 642K
• Fits: Smith & Wesson J Frame Model 642-2 Airweight
• Caliber: .38 S&W Special +P
• Includes: Mainspring Stirrup & Swivel
• Finish: Stainless Steel
• Condition: Used (factory original)
• Installation: Gunsmith fitting recommended

Factory Replacement Quality

Genuine Smith & Wesson factory parts manufactured to the exact specifications and tolerances of the originals — same dimensions, same pivot geometry, same reliable hammer energy transfer. No aftermarket substitutes.

Finding Your Model Number

Swing out the cylinder and check behind the yoke on the frame. Model numbers have been stamped there since 1957–58. If your revolver has no model number, it predates that era — contact us with the serial number and we'll help identify the correct part.

Questions? Call or email us — we're happy to help you get the right part the first time.