I had one as a kid myself. An odd duck it was. IIRC it was referred to as an "automatic single shot". Again IIRC the shooter would retract the charging handle, which held the bolt in the rearward position. The shooter would then insert a single cartridge into the top of the rifle through a spring loaded cover similiar to a loading gate on a lever gun. When the trigger was pulled the bolt moved forward and set off the cartridge. The bolt retracted and locked again automaticlly after each shot. The empty case was ejected trhough a hole in the bottom of the stock.
