This is a copy from the Instruction Manual for the Walther LG300.

Screw C is for the second stage trigger pull pressure. Clockwise is a heavier trigger pull in the second stage.

Screw E is for the sear engagement. Be CAREFUL when adjusting this screw. Better left to experienced users. To adjust : make sure barrel is empty and the rifle is not loaded. Cock the rifle. Turn screw E clockwise until the rifle fires. The turn the screw 1/4 to 1/3 turn back. BE CAREFUL. When you set this incorrectly, the rifle may fire unwanted. Do NOT set this too sharp!

Screw D is for the lenght of the first stage. Clockwise reduces the the first stage.

Screw F is the first stage pressure. Clockwise increases the first stage pressure.

Screws A and B are to move the position of the trigger.