CMMG AR-15 Barrel and Bolt Group Kit Features The CMMG AR-15 Barrel and Bolt Group Kit bundles a 9 .22 LR barrel with a matched bolt carrier group so an existing AR-15 upper can be converted to rimfire without sourcing parts separately. The stainless steel finish on both the barrel and bolt carrier group resists the fouling and corrosion that come with repeated rimfire use keeping the action cycling reliably over time. Because the kit is built specifically around the AR-15 platform installation only requires swapping the barrel and bolt carrier group rather than building an entirely new upper. CMMG backs the kit with a manufacturer limited lifetime warranty for long-term peace of mind. For best function CMMG recommends a round style hammer rather than a notched hammer since notched hammers can cause reliability issues with the lighter rimfire bolt. Thirty-six grain plated round nose bullets have proven to be the most reliable choice for cycling the action smoothly. With only a magazine needed to complete the setup this kit turns a centerfire AR-15 into an affordable training and plinking rifle. The CMMG AR-15 Barrel and Bolt Group Kit is available for sale at GrabAGun for shooters looking to add low cost rimfire practice to their AR-15 platform. CMMG AR-15 Barrel and Bolt Group Kit Specifications Manufacturer: CMMG Model: AR-15 Barrel and Bolt Group Kit Caliber: .22 LR Barrel Length: 9 Compatible Hosts: AR-15 Type: Bolt Carrier Group Material: Stainless Steel Color: Silver / Black Country Of Origin: USA Warranty: Manufacturer Limited Lifetime Available At: GrabAGun