Highest quality bcg i've used - Gemtech Suppressed Bolt Carrier Drop-In Replacement 5.56mm 4347825

This bolt carrier group is really slick. The 2 settings (normal and suppressed) are easy to switch between and function flawlessly. I have used Yankee Hill Machine, BCM, and your run of the mill Bushmaster but this one takes the cake easily! The suppressor setting does a great job of reducing the gas that gets blown back into your face. I would highly suggest this especially if you plan on suppressing your AR.