Hi everyone, I see several problems in the photo. 1.) Because of your fault, the hole before using the button is roughly drilled, this gives risks around the barrel. The hole inside should be like a mirror. 2.) on the rifling on one side there is an overlap of metal, this is due to the fact that the button does not have a second working calibration surface, which follows and removes this overlap. But you can also remove it manually after certain skills ..