BCM's bcg's a good, w/o a doubt but really nothing special.............plenty just as good for similar prices.
For a comparable top-shelf bcg, Griffin Armament just had theirs on sale for around $130ish & Rubber City Armory regularly has blems available for a good price & a really high quality part.
And I'll take nitriding over phosphate (BCM) any day, especially for cleaning of the bolt stem.
MM
