Cornerstone; “the chief foundation on which something is constructed or developed” When you want to start your AR build, the lower is the starting point. The fit and finish of our cornerstone will prove to you that you have the right beginning to a reliable and strong AR build. When coupled with our Grey Ghost Precision uppers, the match is very hard to beat.
Machined to tighter than Mil-Spec tolerance, the critical tooling dimensions are held to within +/ - .001"
Machined from forged 7075-T6 Aluminum
Black Hard anodized with a surface hardness of 60 Rockwell
Features a nylon tipped tensioning screw to ensure the solid fit between upper and lower maintains for years to come.
Functions with nearly all available AR parts kits and uppers.
Flared mag well
Pictogram safe and fire indicators
Chevrons on the front of the mag well and the distinctive Grey Ghost markings tie the Cornerstone to Rifles from Grey Ghost Precision.