Carter, I found the barrel pivot screws on my AirTact were a bit too short. I got 4 mm longer ones (with Allen heads) at the hardware store and added zinc plated steel washers between the star washers and stock. My thinking is that the star washers will keep the tension and the zinc-plated washer will let it pivot smoothly without chewing up the stock. Loctite to keep them from backing out. No need to mess with replacing plastic bushings, right?