In Part 5, I finally got the barrel headspaced, drilled and pinned into the trunnion that I had previously riveted into the receiver. My AK-74 project was finally looking like it would turn into a functional rifle. The next step is to fit the rear sight block, gas block, and front sight block onto the barrel, then drill and pin them into place. AK Parts & Accessories (56) AR-15 Parts & Accessories (150) AR-15 Barrels/Uppers (1) AR-15 Non-Rotating Trigger/Hammer Pin Sets (25) AR-15 Trigger Systems (20) Machine Gun Accessories (23) Pivot/Takedown Pins (57) Spare/Replacement Parts & Accessories (59) Trigger/Hammer Pins (15) Bipods & Accessories (3) CLEARANCE (9) CZ USA EVO/Bren (13) KNS ... Barrel, 7.62 x 39, 16-1/4", Stripped, Chrome-Lined, Used (Press & Pin Type) Product #: 1251990 Shipment prohibited outside USA. Slide the barrel through the wrench, insert the Torque Tool in the back of the receiver until the teeth lock into the locking lugs in the barrel extension, and apply torque with the torque drive through the Tool to tighten the barrel nut. Precision machined from heavy-duty steel bar stock for years of reliable service. Available for the AR-15/M16.