A novel and unique pneumatic paintball marker having a variety of novel features, the first being an on/off compressed air control valve, positioned at the front of the marker below the barrel and adjacent to an in-line pressure regulator. Major innovations have been made in reducing the size and weight of the body of the marker, along with the construction of a new bolt assembly consisting of just four components and only one moving part. An anti-chop eye electronic system insures that the paintballs are in proper position, and rubber ball detents are optionally added to hold the paintballs in place prior to firing the marker, so that the paintballs will not roll out the barrel.