Working...

Your Cart

  • Your cart is empty

Back


HK

HK 51000384 MR556 Upper Receiver Kit 5.56mm for AR15/M16/M4

Product Code : 642230270213

$2,417.99

Mfg Item #: 51000384

Available Online
Secure online ordering

This kit includes a complete upper receiver/barrel assembly, allowing Mil-Spec 5.56mm AR-style rifles to be retrofitted to HKs piston and pusher rod system. This system utilizes a piston and a pusher rod in place of the gas tube normally found in AR15/M16/M4-style rifles. This closed system virtually eliminates the malfunctions that are common in direct-impingement gas systems, since hot carbon fouling and waste gasses are not propelled into the receiver area to operate the action. This is the same key feature critical to the success of the HK416 used by elite military and law enforcement customers. Upper will ship in HK Soft case.

Shipping WidthY
Shipping Length4.38

Determined at checkout.

this site is in
test mode
logo

Some US states prohibit perceived advertising or marketing of firearm related products to persons under 18 years of age.

Are you 18 years of age or older?

Legal Compliance Disclaimer

At SG3 Gunworks, LLC, we comply with all federal, state, and local laws regarding the sale of firearms, magazines, ammunition, and accessories.

It is the buyer’s responsibility to know and follow all applicable laws in their area before placing an order. We do not ship products to locations where they are prohibited, and any such orders will be canceled.

By purchasing from SG3 Gunworks, LLC, you certify that you are legally allowed to own the items ordered and will use them lawfully. Please review your state and local laws or contact local authorities if you are unsure about any restrictions.

*A restocking fee may apply to any orders that do not comply with federal, state, or local regulations.