NSW man charged over grandma killing

A 63-year-old man has been charged with murder over the shooting death of a great grandmother in Sydney's west last year.

Helen Dawson Key, 75, was shot through the front door of her Toongabbie home just before 6pm on November 19.

Her body was found by a friend the next morning.

Police charged a man with murder on Monday afternoon.

Detective Superintendent Michael Willing said the home's front door was open but the screen door was shut, suggesting Mrs Dawson Key might have answered a knock at the door.

The man was refused bail to appear at Blacktown Local Court later on Monday.