Connor and Michael Goodwin were found guilty on Wednesday of killing Anthony Sargeant in a drive-by shooting in August 2018.
The 33-year-old had been talking to a friend in Lee Bank, Birmingham, when a BMW and Mercedes pulled up and two shots were fired. One hit Mr Sargeant in the back and he died six days later in hospital.
Painstaking recovery of CCTV and mobile phone traffic linked the defendants to the cars in the build-up to and aftermath of the killing.
Connor, 27, and Michael, 26, of Wallace Road, Oldbury, were found guilty of murder alongside Keenan Anderson, 25, of Albert Road, Handsworth, and 22-year-old Leon Riley, 22, of Bridgelands Way, Perry Barr.
As part of the investigation, detectives from West Midlands Police uncovered images showing the four celebrating Connor Goodwin’s birthday on the afternoon of August 26 at a pub in Hockley, less than 24 hours after the shooting and while Mr Sargeant lay dying in hospital.
The gun used in the shooting was recovered during a police raid in Derbyshire in November, 2019.
Experts from the National Ballistics Intelligence Service (NABIS) were able to prove it was the same weapon used to kill Mr Sargeant using unique markings on the weapon.
Detective Inspector Hannah Whitehouse, senior investigating officer, said: "We may never know why Mr Sargeant was murdered, but we have been able to prove that these men acted together, travelling in a convoy of two stolen cars across Birmingham to go to Rickman Drive, where Anthony Sargeant was shot.
"They have shown no remorse, denying the offence throughout. This investigation has been highly complex and challenging and it shows that West Midlands Police will relentlessly pursue those responsible for using firearms on our streets.”
Today, Mr Sargeant’s family said: "Almost four years ago, my son, our father, brother and uncle was murdered as he innocently walked down the road outside his mother’s home.
“Today after sitting through months of trial, we finally have justice for him although it will never be enough. However, we still have to live through a lifetime of pain and heartache of him being taken away from his family.
"Eight fatherless children now finding their way through life without their provider, teacher and superhero. Anthony was such a bubbly, energetic, witty soul and we will do everything to ensure he is not forgotten."
They added: "Finally, we would like to thank West Midlands Police for bringing the case before Birmingham Crown Court and the Crown Prosecution service for their outstanding efforts within this case.”
Ian Head, NABIS Head of Intelligence, Governance and International Development, said: “Firearms very often move around the UK from place to place and from crime group to crime group and once recovered NABIS are able to ballistically link them to previous firearms discharges.
"Evidence recovered from scenes allows NABIS to forensically link firearms that have been used in previous shootings. Upon receiving the evidence into our facilities NABIS forensic experts are able to connect scenes using state of the art technology.
"Firearms have unique markings in a similar manner to fingerprints that enable this forensic examination to take place. NABIS analysts then disseminate this ballistic intelligence to Senior Investigating Officers to assist with convictions as in this case."