With the crazy price of .223 and .556 ammo these days , I started looking into alternatives for getting the ARs to the range. I came across the CMMG .22 exchange kit and tried it out today. I brought 3 ARs and used Aguila .22 Super Extra ammo. They ran fine and I had no real problems other than the optics, being zeroed for .556 at 50 yds, were off for .22 at 50 '. I found it much better than using my M&P15-22, as you can manipulate the controls , and feel the weight of an actual AR. I would recommend this kit, and although it is around $200, it won't take long to pay for itself in ammo savings.