Where does your brass land?

Get some 1911 recoil bufers and install at both fore and aft on the op rod, and that should cure a Mini launching brass the length of the firing line. If that dosen't work, you can check out a guy called "Walkenbear" on perfectunion.com for some new gas bushings...try the 0.42 they are right in the middle size wise...Your problems will be cured for sure then. but start out with the 1911 recoil buffers first.

Both of these fixes seem to help out accuracy too.

with the browning sa 22 22lr semi-auto, they end up in the sleave of your shirt