Twenty-twos are not only cheaper than most all center-fire loads, but shooting them is fun. CMMG offers a conversion kit capable of running .22 Long Rifle cartridges in .223 Rem.-chambered AR-15-style rifles. The kit utilizes a stainless steel bolt carrier group and one polymer AR-15-conversion 25-round magazine. Simply swap the carrier group and load the detachable magazine with your favorite high-velocity rimfire loads. The kit also includes a charging handle, forward assist adapter and a cleaning jag guide. Price: $280. Contact: CMMG, Inc.; (660) 248-2293; cmmginc.com.