I have a Stoeger X20 which I bought in 2013. It was pretty accurate in the beginning. I began to have accuracy problems like going off zero 4 to 5 inches up or down. I thought that the rifle recoil had damaged the Stoeger 3-9x32 scope that came with the rifle. I have other guns so I didn't bother with it for quite a while. Recently tried it again with the same results. It would shoot fine then go off 4 to 5 inches. I tried another scope and it happened again. The scope I used was another cheapie. I just got a Leapers UTG 4-16x40 scope and tried it on the gun. The same thing happened. Now I was quite sure that it was the gun. I noticed that the barrel seemed to be sagging and not lined up with the spring tube. I fired some rounds grouping ok. Then the POI jumped again. I checked the barrel and it now appeared to be lined up with the spring tube. I was keeping track of the alignment angles between the barrel and the spring tube. The barrel had moved up 2mm. I was only shooting about 10 meters and the variation was over 4 inches. I don't know how to fix this. I hope that this helps someone.
