K Frame Strain Screw Round Butt Old Style 64172B

Smith & Wesson K Frame Strain Screw - Round Butt, Old Style

Factory OEM strain screw for Smith & Wesson K Frame revolvers with round butt grips. This essential component secures and allows adjustment of the main spring (hammer spring) tension, directly affecting trigger pull weight and hammer strike force.

Specifications:

• Frame: K Frame
• Grip Style: Round Butt
• Design: Old Style
• Condition: Used, factory original

Compatible Models:

Fits K Frame revolvers with round butt frames including Models 10, 12, 13, 15, 19, 64, 65, 66, 67 and other round butt K Frame variants. The strain screw is interchangeable between both centerfire and rimfire K Frame models with round butt grips.

Function:

The strain screw threads into the bottom of the grip frame and retains the main spring. By adjusting the strain screw in or out, you can increase or decrease main spring tension, which affects trigger pull weight and hammer strike force. Proper adjustment ensures reliable ignition while maintaining a comfortable trigger pull.

Round Butt vs Square Butt:

Round butt K Frames have a shorter, rounded grip frame for better concealment. This strain screw is specifically for round butt models. Square butt models use a different length strain screw.

Installation Note:

Installation requires removal of the grip panels. The strain screw should be adjusted carefully to achieve proper main spring tension - too loose can cause light primer strikes, too tight can result in heavy trigger pull.

Note: This is a genuine Smith & Wesson factory part in used condition. Compatible with all round butt K Frame models regardless of caliber (centerfire or rimfire).