Cem Duzgan, 21, was shot 11 times with a sub-machine gun as he played pool at a Turkish social club in Upper Clapton Road, Hackney, east London in 2009.
The victim, who lived with his family in Islington and worked as a sales assistant, died at the scene. He is not believed to have been the gang's intended target.
The murder was part of a spate of tit-for-tat violence, including other killings, between the Tottenham Turks and the Hackney Turks gangs. Just three days before Mr Duzgan's murder, a man was killed in an attack in Tottenham.
Blaize Lunkula, 28, of no fixed address, who was found guilty of murder on February 27 at the Old Bailey, was sentenced to a minimum of 35 years.
Yusuf Arslan, 24, also of no fixed address, was sentenced to a minimum of 33 years; Ndombasi Makusu, 27, of no fixed address, was jailed for no less than 28 years; and Christian Barabutu, 22, of no fixed address, was jailed for a minimum of 18 years.