Swan Machine is a family owned machine shop from Northern Minnesota that specializes in manufacturing firearm components. Our mission is to create high quality products, for a fair price, deliver on time, and maintain excellent customer service. AR-15 Components: (Multiple Calibers) Bolt Carrier Group (BCG's) Bolt Carrier Bolts Gas Key's Firing Pins Cam Pins Extractors Barrel Extensions Muzzle Brakes Pistol Slides Frames (less)