NOT KNOWN FACTS ABOUT BCM LOWER RECEIVER

bcn complete lowerAppeared it above so again and again and will't locate the blem. Everytime I think I locate a thing off, it is simply oil smudges. Most effective guess at this point is scuffs on castle nut, or the two tiny silver spots within the flare in the magwell. 1mm dots at most. BCM QC will not mess all over It appears.Essential an LPK plu