Steyr AUG A3 design details and wear at 1000 rounds. I included some AR parts for comparison since many people are more familiar with those. Steyr AUG A3 with Surefire X300 on the side rail, Aimpoint Micro on a KAC mount and HK416 sights as BUIS. Basic field strip into groups. Barrel group, stock group, receiver, recoiling parts, hammer group, buttplate, light, mag, and sling pin. Barrel group detail stripped. Barrel, gas regulator, gas piston, gas piston return spring. Detail of barrel locking lugs. Detail of chamber area. Detail of gas regulator. Detail of front of receiver. The barrel front trunnion, gas piston bushing (left), charging handle bushing (right), and barrel lock (lower right) all have steel inserts for wear. Detail of rear of receiver. The guide rods run in steel inserts pressed into the receiver. The rear trunnion is a steel insert pressed into the receiver rear. Detail showing rear trunnion barrel locking lugs. Recoiling parts group detail stripped. Firing pin, bolt sleeve, cocking piece, extractor pin, extractor, bolt, and bolt carrier. Firing pin (lower) with AR firing pin for comparison. Bolt with captive cam pin. Detail stripped bolt showing roll pin that captures the cam pin. With AR bolt and parts for comparison. AUG extractor (hard chromed) with AR extractor. AUG extractor is wider and longer. Width of AUG extractor. Width of AR extractor. AR bolt with AUG bolt for comparison. AUG bolt lug dimensions. AR bolt lug dimensions. More in part 2.