I had the same problem with bushnell 3 years ago on a banner scope. wandering zero on a new scope. Got the bent tube excuse, trouble was after they returned the scope I put it in a set of v-blocks and did a run out on the tube and objective lens and could not detect any bend. After several calls to bushnell I got no satisfaction. I have several bushnell products that I use regularly that have provided great service and I will use them until they break, but I will not buy anymore Bushnell products. Nikon, leupold, burris, and weaver all make quality optics and are sure to make a model to fit any of my needs.