ComGraf's patented (Patent #9,651,327) CGAR15FM lower receiver is manufactured from an AR-15 7075-T6 forging. It incorporates a single 1/4" diameter hole through the left wall of the magazine well instead of the normal slot which would otherwise hold a standard magazine catch. The oval counterbore for the magazine catch button on the right side of the receiver has also been eliminated. The magazine is held in place using a small 8-32 button head screw and a special hardened steel retention nut that passes from the inside of the magazine, through the retention slot in the magazine sidewall, and finally through the 1/4" diameter hole. This method of retaining the magazine is functionally identical to that of the standard magazine catch except that it does not allow the magazine to be easily installed or released. Our GEN2 model, in production since January 2018, also incorporates a 10-32 set screw located just behind the pivot pin, providing a "belts and suspenders" approach to CT compliance. (Shown in two center pictures to left.) We call this added screw our "A-Lok" device. In contrast to some other fixed magazine solutions, the CGAR15FM GEN2: (a) naturally positions the magazine vertically in the magwell exactly where it should be, promoting consistent loading of rounds; (b) carries all handling and operational loads through a robust retention nut and screw assembly that won't let your magazine come loose; (c) doesn't require removal of the stock, the safety and the hammer if/when you wish to remove the magazine for cleaning or maintenance, and (d) magazines can only be installed when they are empty. When installed properly, the magazine still "floats" inside the magwell in the same way a magazine floats in a standard AR lower. Additionally, the magazine well has been machined using a combination of wire EDM and CNC machining (instead of through broaching) to restrict loading magazines from the bottom of the receiver.
Stripped lowers and lower assemblies can be purchased here:
Complete lower receivers can also be purchased from the stocking dealers listed here:
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