S&W Model 1940 Light Rifle Mk II
Smith & Wesson · Submachine Gun · Out Of Production · 1940
Also known as: Smith & Wesson Light Rifle, S&W 9mm Light Rifle, Smith & Wesson Mark II
Overview
The S&W Model 1940 Light Rifle Mk II is a semi-automatic, blowback-operated 9x19mm submachine gun (light rifle carbine) built by Smith & Wesson for Great Britain in 1940. Firing from an open bolt and fed from a front-loading 20-round box magazine, it was an exceptionally well-machined but flawed weapon: its deeply threaded receiver cap left a thin wall that the bolt hammered against on every shot, fracturing after roughly 1,000 rounds. The Mk II replaced the Mk I's floating firing pin and bolt-mounted hammer with a fixed firing pin intended to handle hotter British military 9mm loads. Britain rejected the design and the program was cancelled, making surviving examples extremely rare.
Specifications
| Weight (empty) | 4080 g (143.9 oz) |
| Overall Length | 813 mm (32.01") |
| Barrel Length | 248 mm (9.76") |
| Action Type | Blowback |
| Firing Mechanism | Open Bolt |
| Trigger Type | Single Action |
| Magazine Capacity | 20 rounds |
| Magazine Type | Detachable Box |
| Muzzle Velocity | 365 m/s (1198 fps) |
| Muzzle Energy | 481 J (355 ft·lbf) |
| Effective Range | 100 m (109 yd) |
| Barrel Rifling | Right Hand |
| Frame Material | Steel |
| Slide Material | Steel |
| Barrel Material | Steel |
| Stock Material | Walnut |
| Finish | Blued |
Calibers
- 9x19mm Parabellum · primary · 9mm NATO — also known as 9mm Luger, 9mm NATO, 9x19mm
Features
- Firing modes: Semi Automatic
- Feed systems: Detachable Box Magazine
- Safety mechanisms: Manual Safety
- Features: Front Loading Magazine Well, Fluted Barrel, Milled Steel Construction, Integral Brass Cartridge Chute
Variants
- S&W Model 1940 Light Rifle Mk I — Earlier Pattern
Service history
Operators
- British Purchasing Commission · adopted 1940
Conflicts
- World War II (1939-1945)
Production
Estimated total produced: 1,227 · Production years: 1940
Approximately 950 rifles were delivered to Britain across the Mk I and Mk II patterns before the program was cancelled; total manufacture is generally cited at around 1,200 units.
Origin
Country of origin: United States
Discontinued: 1940
Notes
Strictly semi-automatic only despite its open-bolt, magazine-fed submachine-gun layout. Roughly 950 rifles were delivered to Britain. The fluted barrel, milled construction, and integral brass cartridge-ejection chute made it expensive and over-engineered for a wartime stopgap. The British destroyed most of their stock; a small number left at the factory were later sold in the US as Curio & Relic items.
Background
Conceived as a quick way for Smith & Wesson to repay a British advance for a never-delivered .45 revolver contract, the Light Rifle became one of the company's costliest failures. After the British rejected and destroyed the rifles, the remaining factory stock was effectively buried until later collectors rediscovered it.