I did a bit of shooting today and noticed the sidelever was opening slightly during the shot. I have the rubber ball in the right place i imagine anything i should check?
Here is your problem. The reloading block pin sometimes bend and make the hole in the linkage (part A11 I think) larger. I had to change reloading block and lever linkage to fix the problem. If your reloading block pin in good shape, just change the lever linkage.