Arisaka Defense Zero Retention Clamp for MCX Spear .308


In stock

SKU: ZRC-SPEAR-H UPC: 850036188667

Product Description

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 Spear. This version is designed for the MCX Spear chambered in 277 Fury and 308.

The MCX Spear handguard is not adequately secured to the upper receiver. 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 10 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 its original position once pressure is removed from the handguard.

The Arisaka ZRC consists of two sets of 7075 clamps that mount in the vent slots on either side of the handguard. The inner half of each clamp engages the extended upper receiver. This secures the handguard tightly to the upper receiver across two axis, greatly reducing the zero shift. The clamps do not touch the barrel or gas system, preserving the free-floated barrel. A pair of tapered head screws are also included to replace the handguard retaining button head screws on each side of the receiver. This eliminates forward/rear and vertical movement at those two contact points.

The ZRC clamps are contoured to provide minimal interference with the user’s hands while gripping the handguard.

Arisaka is not responsible for any damage caused by improper installation. The ZRC must be uninstalled before removing the handguard from the rifle.


  • Compatability – MCX Spear 277, 308
  • Weight: 2 oz.
  • The ZRC clamps are CNC machined from 7075-T651 aluminum
  • MIL-A-8625 Type III hard coat clear anodized, resulting in the tan/gold color.
  • Made in the USA.

Installation Instructions




Technical Information

Color / Pattern




7075 Aluminum



Firearm Compatibility

Catalog Location

California Prop 65 Warning

WARNING: This product can expose you to chemicals, which are known to the State of California to cause Cancer and Reproductive Harm. For more information visit