Smith & Wesson M&P 40 Shield Locking Block .40 S&W Used Part 40S6
Smith & Wesson M&P 40 Shield Locking Block — .40 S&W | Part #40S6
This listing is for a genuine Smith & Wesson factory locking block for the M&P 40 Shield chambered in .40 S&W. This is a used OEM part in good working condition — a cost-effective solution for gunsmiths and owners needing a reliable replacement without paying new part prices.
The locking block is a critical fire control component that locks the barrel into battery during firing. Replacing a worn or damaged locking block restores proper function and maintains factory tolerances.
Part Details
- Part Number: 40S6
- Condition: Used — good working condition
- OEM: Genuine Smith & Wesson factory part
- Caliber: .40 S&W
Model Compatibility
| Model | Generation | Caliber | Compatible |
|---|---|---|---|
| M&P 40 Shield | 1.0 | .40 S&W | ✓ Yes |
| M&P 40 Shield | 2.0 | .40 S&W | Verify fitment |
Note: Not compatible with M&P 40 full-size, M&P 40 Compact, M&P 40 Shield EZ, or M&P 40 Shield Plus. Shield-specific part only.
Installation Notes
- Gunsmith installation recommended
- Full disassembly required for replacement
- May require fitting by a qualified gunsmith
- Manufactured to exact factory specifications
Questions? Contact our firearms parts experts at sales@usagunsandgear.com or call 770-544-8075.
No shipping outside the U.S.