Geissele Super Duty with 100,000 rounds through it
This Geissele Super Duty upper receiver endured 100,000 rounds, revealing critical wear points. Significant findings include a worn cam pin cutout in the upper receiver, a 'shot out' barrel with eroded gas port and throat, and multiple component failures in the Bolt Carrier Group (BCG), such as broken extractors and ejector springs. The gas key also showed severe erosion and leakage.









