HK MR556 A4 SBR 11"
Factory 11-inch stock-equipped SBR variant of HK's MR A4 line, model 81001048 with one 30-round magazine; distinct from the 11-inch MR556 A4 pistol model 81001050.
- Price
- $4,299
- Weight
- 6 lb 11 oz
- Calibers
- 5.56x45mm
- Rail
- mlok
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Key Highlights
- •Factory 11" MR A4 LE SBR configuration
- •NFA registration required; federal SBR making/transfer tax is currently $0
- •Adjustable gas regulator makes it an exceptional suppressor host at short barrel length
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Overview
The MR556 A4 SBR is HK's factory 11-inch stock-equipped short-barrel rifle in the MR A4 family. It keeps the MR A4 short-stroke piston operating system, adjustable gas regulator, and ambidextrous controls in a shorter configuration than the 16.5-inch rifle. This semi-automatic civilian model is an HK416-family analog, not an exact issued HK416. HK identifies it as an NFA-regulated item.
Key Features
- 11" cold hammer-forged barrel, 1:7 twist, 1/2x28 threads
- Short-stroke gas piston with 2-position adjustable gas block
- Fully ambidextrous controls
- HK Free Floating M-LOK Rail System
- Optic-ready full-length Picatinny top rail
- Tungsten-filled proprietary buffer (designed for short-barrel gas curve)
- Available in 10- or 30-round configurations depending on SKU and jurisdiction
- Same MR556 A4 lower as the 16.5" rifle (parts compatibility)
Capability Profile
0-10 Scale Across 8 Axes
Pros
- +Factory-built SBR — no Form 1 build, no pinned-and-welded muzzle device
- +Factory 11" MR A4 SBR configuration
- +2-position adjustable gas block handles suppressor pressure changes cleanly
- +Short-stroke piston keeps the action cooler than DI in 11" configurations
- +Same proven HK QC as the 16.5" rifle
Cons
- −NFA item — requires Form 4 transfer and registration paperwork
- −MSRP is one of the priciest factory 5.56 SBRs available
- −11" barrel sacrifices muzzle velocity (~2,650 fps with M193 vs ~3,100 fps from 16")
- −Proprietary barrel and gas system limit aftermarket length swaps
Detailed Specifications
- caliber
- 5.56 NATO
- Barrel Length
- 11"
- Overall Length
- 27.9" - 31.7"
- weight
- 6.7 lbs
- Gas System
- Short-stroke gas piston with 2-position adjustable gas block
- railSystem
- Slimline M-LOK handguard with 16.75" Picatinny top rail
- Trigger
- Two-stage, 4.5-5.6 lb approximate
- Twist Rate
- 1:7 right-hand, 6 lands & grooves
- threadPitch
- 1/2x28
- msrp
- $4,299 (SKU 81001048 / 81001049)
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