Smith & Wesson K Frame Model 10 Strain Screw Square Butt Blue Steel Old Style Used Part K10172B

Smith & Wesson K Frame Model 10 Strain Screw — Square Butt | Blue Steel | Old Style | Used | Part #K10172B

Factory OEM strain screw for Smith & Wesson K Frame Model 10 revolvers, square butt configuration, blue steel finish, old style design. The strain screw threads into the bottom of the grip frame and bears against the main spring, allowing adjustment of hammer spring tension. Genuine S&W factory part in used condition.

This listing is for the strain screw only. Condition: Used, factory original.

Specifications

• Part Number: K10172B
• Frame: K Frame
• Model: Model 10
• Caliber: .38 Special
• Grip Frame: Square Butt
• Design: Old Style
• Finish: Blue Steel
• Material: Steel
• Condition: Used / Factory Original OEM

Model Compatibility Chart

Important: This strain screw is specific to square butt K Frame Model 10 revolvers. Square butt and round butt grip frames use different strain screws — they are not interchangeable. Verify your revolver’s grip frame configuration before ordering.

Function

The strain screw threads into the bottom of the grip frame and contacts the foot of the main spring (hammer spring). Tightening the screw increases spring tension, resulting in a heavier trigger pull and more reliable primer ignition. Backing the screw out reduces spring tension for a lighter trigger pull, but risks light primer strikes and misfires. Factory specification is fully seated. Only adjust with caution and verify reliable ignition after any change.

Installation Note

Strain screw replacement requires grip panel removal. Use the correct screwdriver to avoid damaging the screw head. After installation, verify reliable primer ignition with your chosen ammunition before carrying or using the revolver for defensive purposes.