(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
$3,799.00
HK 81001033 MR556 A4 5.56x45mm 10+1 16.50″ Black Barrel, Black Receiver w/Picatinny Rail, Black Polymer Stock, Black Polymer Grip, Ambidextrous
Available to order: Out of stock
The HK-USA MR556 A4 chambered in 5.56x45mm, its 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 than direct-impingement ARs. 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 A4 easier to operate, manipulate and employ. Includes one 10rd magazine.
| upc | 642230269422 |
|---|---|
| manufacturer | Heckler & Koch / H&K |
| Manufacturer Part Number | 81001033 |
| Action | Semi-Auto |
| Barrel Length | 16.5" |
| Caliber/Gauge | .223 REM/5.56 NATO |
| Capacity | 10 + 1 |
| Number of Magazines | 1 10 rd. |
| Product Type | Rifle |
| Rate of Twist | 1:7" |
| Safety | Selector Switch |
| Shipping Weight | 0.0 |
| Sights | No Sights |
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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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