NSW man charged after shooting himself

A man has been charged with firearms offences after he allegedly shot himself with a key-ring gun by accident in Sydney's southwest.

Ambulance officers were called to a house at Doomben Close, Casula at 8:30 pm (AEDT) on Thursday after reports a man had discharged a firearm in the garage.

He was treated on the scene and transferred to Liverpool hospital where he was questioned by police.

Police say they were told the man was holding a key-ring gun when he accidentally shot himself in the finger.

They established a crime scene at the house where they allegedly found a firearm and ammunition.

The 37-year-old man was released from hospital Friday and charged with a number of firearms offences including two counts of possessing or using a weapon without a permit.

He was also charged with one count of possessing a prohibited drug.

The man was granted conditional bail and is due to appear in Liverpool Local Court on February 19.