My storm was in need of work . The chrony test showed it was only putting out a average of 558 with CP 7.9 domes and 453 with CP 10.5 domes . I tore it down and found a burnt seal and bent spring. I used crosman factory parts spring, seal , brake joint washers , bushing and bolt . I decided to re - do the stock as well . I also had a POI shift problem and that's why I replaced the bushing and bolt. Today at the range it did better with open sights but I will not know for sure about the POI problem until I scope it latter this week . I did make a spring spacer for it and the chrony reading did improve. CP DOME 7.9 averaged 885 and the 10.5 averaged 762 . I also shot 2 Gamo rapers through it that were given to me and they were 1086 and 1092 FPS . I have included pictures of the stock before and after the re-do as well . Marvin