Barrel Polishing Service for Automatic Pistols: Another Free US RGC Service. Barrel Polishing adds another level of realism to your replica or Blank Firing Pistol. This looks great on the 1911, and other enclosed slide Pistols like the Walther PPK, the Beretta Model 8000, Browning High Power, and the Beretta Px4,,,Not recommended for open Slide guns like the Beretta Model 92.