The NSW Police Force's forensic ballistics unit are expected to analyse the bullet recovered from a Raymond Terrace house on October 3 and a second pulled from a Fern Bay car last Wednesday, October 8.

Police said it was not known at this stage whether the two incidents were linked. No one was injured in either incident.

The first shot was fired into the lounge room window of a Hillside Crescent house sometime on October 3, police said.

The second was fired at a Nissan Pulsar sedan parked outside a home along Nelson Bay Road at Fern Bay sometime between 2pm on October 3 and 7am on October 8.

Police said the bullet passed diagonally through the car - entering in from the outside of the rear driver's side door, through a child's car seat, and lodged in the rear passenger side door.

The owner of the car, a Fern Bay woman, was only alerted to the damage after her partner drove the vehicle to work and a colleague pointed out the puncture.

Police were called and the car examined. Both bullets were sent to the forensic ballistics unit for analysis.