CMMG Conversion Kit, Bravo, Fits AR Rifles, 22LR, 10Rd 22BA62F Just swap this drop in conversion with the bolt carrier group from your 5.56/.223 chambered rifle and you will be ready to shoot .22LR. Ships with a 10rd Magazine. For best performance use a round style hammer as notched hammers can cause function issues and 36 grain plated nose bullets have proven to be the best choice for function.