You might want to check out this thread: Handloading for the AG42b Ljungman Rifle

Many of us have found that installing an adjustable gas screw on the Ljungman is a nice way to keep the brass from being ejected into the next city, and not too hard to do once you find the right size screw. This way you can adjust for how far the ejected brass is thrown after you find your best load: Ljungman AG42b Gas Regulator