BCM LOWER RECEIVER THINGS TO KNOW BEFORE YOU BUY

bcn complete lowerLooked it in excess of so many times and can't discover the blem. Everytime I feel I find a little something off, it is just oil smudges. Very best guess at this point is scuffs on castle nut, or The 2 tiny silver places from the flare of the magwell. 1mm dots at most. BCM QC will not mess all over It appears.this is the fifth BCM