Smith & Wesson K Frame Model 17 Hammer Block - Stainless Steel
Part Number: K503
Condition: Used - Good
Frame: K Frame
Model: 17 K-22 Masterpiece
Caliber: .22 LR
Finish: Stainless Steel (S.S.)
Type: Hammer Block (Firing Pin Block)
Weight: 1 oz
Product Details
Genuine Smith & Wesson factory hammer block (also called firing pin block or safety block) for the K Frame Model 17 revolver. This critical safety component prevents the firing pin from moving forward unless the trigger is fully pulled and the hammer is falling. Stainless steel construction provides corrosion resistance and durability. Essential safety part for your classic .22 target revolver.
About the Model 17
The Smith & Wesson Model 17 K-22 Masterpiece is a legendary .22 LR target revolver built on the medium K Frame platform. Introduced in 1931 (originally as the K-22 Outdoorsman, later K-22 Masterpiece), the Model 17 features adjustable sights, a 6-shot cylinder, and is typically available with a 6-inch barrel. The Model 17 is renowned for exceptional accuracy, smooth trigger action, and reliability. It's extremely popular for target shooting, small game hunting, training, and competitive shooting. The .22 LR chambering makes it economical to shoot while maintaining the feel and handling of centerfire K Frame revolvers.
Hammer Block Function
The hammer block is a critical safety component in modern Smith & Wesson revolvers. It's a spring-loaded piece that sits between the hammer and the firing pin. Under normal conditions, the hammer block prevents the firing pin from moving forward, even if the hammer is struck or the gun is dropped. Only when the trigger is pulled fully to the rear does the hammer block drop out of the way, allowing the hammer to strike the firing pin and fire the cartridge. This is an essential safety feature that prevents accidental discharge.
Safety & Compatibility
The hammer block is one of the most important safety components in your revolver. A worn, damaged, or missing hammer block can allow the gun to fire if dropped or if the hammer is struck. This part should be inspected regularly and replaced if worn. Never operate a revolver with a damaged or missing hammer block.
This hammer block is specifically designed for Smith & Wesson K Frame Model 17 revolvers chambered in .22 LR with stainless steel construction. It may also fit other stainless K Frame .22 models - contact us to verify compatibility for your specific revolver.
K Frame .22 Stainless Models
The Model 17 is part of Smith & Wesson's K Frame .22 family. Stainless steel versions are highly sought after for their corrosion resistance and low maintenance requirements. The Model 17 differs from the Model 18 (Combat Masterpiece) primarily in barrel length and sight configuration. Both use similar internal parts, though stainless and blued models may have slight differences.
How to Identify Your S&W Model
To determine your Smith & Wesson revolver model number, swing out the cylinder and check behind the yoke on the frame for the model number stamped into the metal. You should see "17" or a dash variant like "17-1", "17-2", etc. Model numbers began in 1957-58. If no model number is present, your revolver may be a pre-model K-22. Contact us with your serial number for assistance in identifying the correct parts.
Installation & Specifications
- Professional gunsmith installation strongly recommended
- Requires disassembly of internal action components
- Critical safety component - must function properly
- Improper installation can create serious safety hazards
- Test function after installation to ensure proper operation
- Factory OEM part manufactured to exact S&W specifications
- Used part inspected for wear and functionality
- Compatible with K Frame Model 17 stainless steel revolvers
- May fit other stainless K Frame .22 models - verify compatibility
- Stainless steel construction
- Spring-loaded safety block design
Safety Testing
After installing a hammer block, the revolver must be function tested to ensure the safety works properly. With the gun unloaded, cock the hammer and release it without pulling the trigger - the hammer should NOT reach the firing pin. Only when the trigger is pulled fully to the rear should the hammer be able to strike the firing pin. If the hammer block does not function correctly, do not use the revolver until it is properly repaired by a qualified gunsmith.
Condition Notes
This is a used OEM hammer block removed from a functioning Smith & Wesson Model 17 revolver. Shows normal wear consistent with use. All surfaces have been inspected for excessive wear or damage. Spring tension is good. Stainless steel finish may show minor wear typical of used revolvers. Critical safety surfaces are in good condition. Guaranteed to function properly when correctly installed.
Contact Us
We specialize in Smith & Wesson pistol and revolver parts - used, new old stock, refurbished, and new. Our team has extensive knowledge of S&W firearms and can help you find the exact parts you need for your K Frame revolver.
Questions? Email sales@usagunsandgear.com or call 770-544-8075