(903) 259-6600|Tue–Fri 10am–6pm · Sat 10am–5pm|2510 Hemphill St., Greenville, TX
(903) 259-6600|Tue–Fri 10am–6pm · Sat 10am–5pm|2510 Hemphill St., Greenville, TX
$3,710.99
HK 81001204 MR556 A4 5.56x45mm 10+1 16.50″ Black Threaded Barrel, Patriot Brown Picatinny Rail Receiver, M-LOK Handguard, 6 Position Black Synthetic Stock, Ambidextrous
Available to order: Out of stock
The MR556 A4 short-stroke gas piston operating system does not impart hot carbon fouling back into the action, allowing the weapon to run longer, with less maintenance and with less wear on internal components. Its adjustable gas regulator allows the operator to tune the action specifically for suppressed or unsuppressed operation. Fully ambidextrous controls, lighter weight and a slimmer profile make the new A4 easier to operate, manipulate and employ.
| upc | 642230271081 |
|---|---|
| manufacturer | Heckler & Koch / H&K |
| Manufacturer Part Number | 81001204 |
| Action | Semi-Auto |
| Barrel Length | 16.5" |
| Caliber/Gauge | .223 REM/5.56 NATO |
| Capacity | 10 + 1 |
| Rate of Twist | 1:7" |
| Safety | Ambidextrous Safety Lever |
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October 20, 2026
The $200 tax stamp is gone for suppressors and SBRs, and ATF has stopped enforcing Form 4 approval. Here is what still applies to Texas gun owners.
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October 13, 2026
ATF will no longer enforce Form 4 approval or tax stamps for suppressors, SBRs, SBSs and AOWs. Here's what changes for Texas buyers.
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June 11, 2026
The federal suppressor tax stamp dropped from $200 to $0 in 2026, making suppressor ownership more accessible than in decades.
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