RedactedNarrative: Boat was recently rebuilt and this was one of the first times boat was back on water.  Boat had total of 4 occupants on it at time of incident.  Operator of boat said he was traveling approximately 20mph in choppy water when they noticed water inside the boat.  Operator stopped boat and noticed that boat was filling with water.  PFD's were obtained and put on by all occupants in boat.  Operator called friend for help as well as 911.  Another boat picked the 4 occupants up.  Boat sunk and was nearly completely submerged.  Boat was marked with a buoy and arrangements are being made by owner to have it removed from lake.  No injuries or fatalities as a result of incident and all occupants are accounted for.  No other boats were involved in incident and it does not appear that boat struck any other object.