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Rock River Arms 18 Inch - Varmint A4 Upper


The Rock River Arms 18 Inch - Varmint A4 upper features a Rock River Arms 18 Inch stainless steel, air gauged, cryo-treated bull barrel chambered in .223 Wylde with a 1:8 twist and rifle length gas system.  Built on a Rock River Arms forged A4 flattop receiver with a Rock River Arms TRO-MID handguard and a .936 low profile gas block.

MCR 12.5" Adjustable Heavy Barrel


Complete barrel assembly for use with MCR® rifles and upper receiver assemblies. Includes barrel extension with fixed headspace, gas block assembly, 4 position regulator, piston, flash hider and dovetail cover. 100% Made In USA.

MCR Quick-Change Barrel Handle Assembly


Permits safe and easy handling of hot Quick-Change Barrels! Fits all models of MCR®, Shrike 5.56™ and military AMG-2.

MCR Extended Bolt Catch


Fits in a mil-spec AR15/M4/M16 lower receiver. For use with MCR® upper receiver assemblies, provides the necessary clearance for the wider MCR® upper receiver. Made In USA.