It is a recoil operated gun and the adjustments are made under the forearm, to shoot the lighter sporting loads place the top two friction rings that are located above your recoil spring and place them at the base closest to the receiver rplace spring on top of them, replace forearm , but do not attempt to shoot the high brass loads with the rings like this, you will crack your forearm.

RON KONTOWSKY
DEAN`S GUNSHOP II
GUNSMITHING DIV.