Arisaka Zero Retention Clamp for 5.56 MCX Virtus MLOK Handguard

The Patent Pending Arisaka Zero Retention Clamp (ZRC) greatly reduces zero shift for lasers and iron sights that are mounted on the handguard of the MCX Virtus. The initial version is designed for the MCX Virtus chambered in 5.56mm with either the Sig Sauer OEM slim handguard or Midwest Industries standard M-Lok handguard. A different version for the MCX Virtus chambered in 300BLK and SD handguards is in development.

The MCX Virtus handguard is secured to the receiver by a friction fit slot on each side near the extended receiver top rail and a single steel fitting held in place by the front takedown pin. This allows the handguard to flex significantly, causing a laser or front sight zero to change when minor pressure is applied to the handguard. A shift of 5 mils or more is possible by pushing on the handguard with your support hand while the rifle is shouldered. Additionally, the zero does not always return to it's original position once pressure is removed from the handguard.

Sig Sauer has resolved this problem on the new MCX SPEAR by adding a fastener on each side of the handguard that securely anchors it to the upper receiver. The Arisaka ZRC plays a similar role for the MCX Virtus by clamping the handguard together at the friction fit alignment slots on the extended upper receiver. This secures the handguard tightly to the upper receiver, greatly reducing or even eliminating zero shift.

The ZRC clamps are contoured to provide minimal interference with the user's hands while gripping the handguard. On the OEM slim handguard the clamps fit in the rhombus shaped vents, while on the Midwest Industries standard M-Lok handguard they occupy one M-Lok slot in the top row. Each clamp is labeled for the side and orientation, making installation easy.