I just bought a refurbed Imagine and I have tried about 4 different ball companies in and it has chopped all of them. I have a VL revy, progressive barrel, 20oz tank, and everything else stock. I have lubed all the O rings, turned down the velocity, and shot very slowly. It's still chopping. What am I doing wrong? I have seen people talking about ACS bolts(delrin) but will that help my problem or do I need something else? Is there a temporary fix or something simple?