Genesis Arms GEN-12 10.5'' UPPER RECEIVER 12 GAUGE G12-U10

The GEN12 was not the 1st ""AR shotgun"", but it is the first to use a standard 308 lower. The GEN12 upper was specifically designed to matte to any DPMS GEN1 308 Lower or other 308 lowers sharing the same pattern. The GEN12 upper will work with either the shorter DPMS buffer tube or the longer Armalite AR10®/ 308 tubes. The center of the upper is the short recoil system which cycles the action. This means there is no gas tube or piston. The cyclic rate can be tuned by adjusting buffer weights and springs by the end user.   The upper will cycle birdshot or magnums and most everything in between. It reliably feeds both 2 ¾” shells and 3” shells on a standard short DPMS 308 buffer and spring. However they recommend a H3 buffer or a Hydraulic buffer when shooting magnums or any 3”. These uppers are compatible with SGM Tactical Saiga 12 choke tubes with external threads.    This is sold as an upper so this does not require a FFL to purchase; however, you are responsible to know the laws in your state and purchase accordingly. Some Assembly required: Do to the shock and recoil from the 12 gauge, and the inherent differences within magazine geometry, you will be provided several parts to replace on your DMPS GEN1 patterned lower to ensure functionality and compatibility.   BEEF UP KIT: Magazine catch & increased power spring Bolt catch & increased power spring Anti-rotation trigger pin set ***These parts need to be installed.