Kieran McGrath, 26, managed to drive to the nearby Ashton-under-Lyne police station after being shot outside the Sheldon Arms, but died soon afterwards.
Six people, aged between 18 and 33 have been arrested on suspicion of murder.
A post-mortem examination found Mr McGrath, from Clayton, died from a single gunshot wound to the chest.
Six people have been arrested by police investigating the fatal shooting of a man outside a Greater Manchester pub on 4 October.