With the Charles Daly® AR.410 Upper, any AR-15 can be changed into a.410 shotgun. The 19-inch barrel of the CD.410 Upper has a 2.5-inch.410 bore. It has flip-up front and back sights as well as a forend with a picatinny rail.
Important: This top MUST USE CARBINE BUFFER TUBE and will only function with a MIL-SPEC bottom. For the upper to work properly, the buffer must be utilized with the carbine buffer spring. Damage to the upper and lower can result from failure to shoot without the required buffer and the carbine buffer tube. For optimal performance, the overall cartridge length must be 2.29in or less.