The SIG Sauer MCX Spear SBR is a compact, semi-automatic short-barreled rifle built for modularity and modern cartridge performance. This configuration is chambered in 6.8x51mm with a 13″ threaded barrel and ships with a single 20-round steel magazine. Controls are fully ambidextrous and the platform features a folding Magpul SL-M stock and M-LOK handguard to support a range of accessory and optic setups.
Key Specifications
- Chambered in 6.8x51mm.
- The barrel measures 13 inches.
- Magazine capacity is 20 + 1.
- The action type is Semi-Auto.
- The listed weight is 8.90 lbs with magazine.
- The barrel is described as cold hammer forged steel and threaded.
- The rate of twist is 1:7.
- Stock type is a Magpul Push-Button Folding SL-M stock.
- Operating system uses a gas piston.
- Finish and receiver are coyote anodized.
The MCX Spear SBR packs advanced cartridge performance and a compact, modular package suitable for precision-focused shooters who need a short-profile rifle. Its ambidextrous controls, adjustable gas system and M-LOK forend make it adaptable to a variety of optic and accessory configurations while maintaining a purpose-driven build quality.
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