AR-15 22 LR CMMG ECHO SS ARC KIT with 10 Rd Magazine - Left Hand, Just swap this drop in conversion with your bolt carrier group and you will be ready to shoot .22LR.
The Echo Stainless Steel kit contains:
All CMMG .22 LR magazines have a bolt hold open follower. For best performance use a round style hammer as notched hammers can cause function issues. 36 grain bullets have proven to be the best choice for function. Set up is less than 30 seconds. Ammo is 1/10 of the price of 5.56 ammo, i.e., at significant savings to you.