ORIGINAL: Ridge Runner

remove forend bolt and forend, push out the 2 pins and remove hammer/trigger assembly.

the metal tube between the action rails is the barrel block nut, there is a hole in it, insert a punch or metal rod into the hole and turn counterclockwise to loosen, remove.
slide barrel out till it clears the threaded stud, rotate 90 degrees so the barrel block clears the rails.and lift out.
Now slide bolt/carrier assembly out the front, remove action rails.
if you have the sling mounted to the forend they are probably slightly bent making them bind while cycleing the action, if not possibly bowed out from use.
RR