The shooting in Cannon Street, Bolton, on 10 October was one of four which took place in 24 hours.
Greater Manchester Police said the shooting outside a pub was an "isolated incident".
It was said to be the only one of the four incidents on the day that was not connected to a gang feud in Salford.
A 22-year-old man has been arrested on suspicion of attempted murder over the shooting of a man in the stomach in Greater Manchester earlier this month.