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This kit includes a complete upper receiver/barrel assembly, allowing Mil-Spec 5.56mm AR-style rifles to be retrofitted to HK’s 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.

This kit includes a complete upper receiver/barrel assembly, allowing Mil-Spec 5.56mm AR-style rifles to be retrofitted to HK’s 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.

HK416 A5 Stripped upper receiver housing

Extractor pin for MR556 rifles.

Cam pin for MR556 and HK416 rifles

Originally designed for the US military’s SOPMOD rifle enhancement program, the KAC M4 Folding Front Sight is a low-profile backup sighting solution that is designed to be attached to the top rail of a rifle’s handguard. When stowed in the folded position, the M4’s sight base extends back to envelope the front sight leaf on the right and left side, helping to protect it from damage.

Rear take down pin for MR556 and HK416 rifles.

PIN, RECEIVER PIVOT, HK416 , FRONT

The MOE SL Stock – Mil-Spec Model (MOE Slim Line) is a drop-in replacement buttstock for AR15/M4 carbines using Mil-Spec sized receiver extension tubes. Designed for the modern battlefield, the sleek profile, dual-side release latches, rolled toe, and angled rubber butt-pad are optimized for use with body armor or modular gear and provides for efficient shoulder transitions.