The Heckler & Koch MR556 A4 11" SBR brings the proven HK416 lineage into a compact, semi-automatic package built around a short-stroke gas piston system. Its 11-inch 5.56 NATO threaded barrel with 1/2x28 muzzle interface is paired with a free-float M-LOK handguard and flat-top Picatinny upper, giving shooters a rigid, accurate platform that stays cleaner and cooler than traditional direct-impingement designs. Fully ambidextrous controls, a slimline telescoping stock, and ergonomic polymer grip round out a rifle that emphasizes reliability and intuitive handling.
This MR556 A4 configuration is ideal for shooters who want a premium short-barrel rifle for dedicated range use, training, or duty-style applications where compact size and controllability matter. The adjustable gas regulator supports both suppressed and unsuppressed operation, while the 30-round detachable magazine capacity (where permitted) offers ample time between reloads. With its balanced weight, refined recoil impulse, and attention to detail throughout the MR A4 series, this rifle reflects Heckler & Koch’s longstanding reputation for precision engineering and durable craftsmanship.
Key Features:
- Manufacturer: Heckler & Koch
- Model: MR556 A4 11" SBR
- Caliber: 5.56 NATO / 5.56x45mm
- Condition: New
- Action: Semi-Automatic
- Barrel Length: 11" Threaded 1/2x28
- Number of Magazines: 1
- Capacity: 30 Rounds
- Threaded Barrel: Yes
- Weight: 7–7.67 Lbs (Configuration Dependent)
- Length: Approximately 27.5"–31.7" (Stock Adjusted)
- Width: 3.07"
- Height: 7.5"
| __Model | MR556 A4 |
| __Action | Semi-Automatic |
| __Capacity | 30 |
| __Caliber | 5.56x45mm NATO |
| __Barrel Length | 11.00" |
| __Optic Footprint | NA |