Mohamud Mohamud, 30, Cadil Huseen, 23, and Hussein Ali, 26, pleaded guilty to killing Mohammed Abdi in the Duddingston area of Edinburgh at 1am on May 26 last year.
Mr Adbi, who came to Scotland from Somalia as a teenager, was gunned down in what is understood to have been a feud over drugs, and died from a gunshot wound to the chest.
All three men are now facing life sentences for a crime that shocked the whole of Scotland.
Judge Lord Turnbull said: "This is a level of criminality seldom seen in our country, and mercifully so."
Seven men were initially accused of the murder and were on trial at the High Court in Glasgow for almost four weeks before the three admitted their guilt. Co-accused Ahmed Ahmed, 28, Liban Ahmed, 30, Said Fadal, 32, and Said Tarabi, 27, had their pleas of not guilty accepted by advocate depute Iain McSporran, prosecuting.
Lord Turnbull said he would have to call for background reports before determining how long Mohamud, Huseen and Ali would spend behind bars before being eligible for parole.
Police said yesterday the murder followed a dispute between rival factions of a London-based organised crime group operating in Scotland.
The three men and their victim, who at the time of his death was facing a drugs charge, had been friendly, but there was a falling-out over the tenancy of a flat that was lost, for which Huseen was blamed.
The situation escalated days before the murder when Huseen's flat in Gilmerton, Edinburgh, and that of Ali, in Captain's Drive, Edinburgh, were vandalised.
On the night of the killing witnesses spoke of hearing cars chasing each other along Duddingston Road West, Willowbrae Road and Abercorn Avenue, a VW Sharan crashing into the fence of a nearby tennis court and then the sound of gunfire.
One man described it as a rat-a-tat sound and the noise was heard in the background of one of the many 999 calls made to the police that night.
Another witness, taxi driver Mohammed Irfan, 34, from Edinburgh, said: "I never thought it would be happening here. It was like something you hear in the movies I couldn't believe it would be shots. I heard three loud bangs, which I found out the next day were shots."
A forensic expert told the court that at least five shots were fired from the converted replica machine gun. Another bullet was fired from a converted revolver found in the VW Sharan, but the bullet that killed Mr Abdi came from the machine gun.
Police on a passing patrol initially thought there had been a car crash but quickly realised Mr Abdi had been shot. He was pronounced dead at the scene and a murder hunt was launched.
Detectives used telephone records to trace the journey of some of the members of the gang, who had travelled from London to Glasgow and then on to Edinburgh. The route of the cars was followed using CCTV cameras and forensic analysis of the VW Sharan revealed the identity of some of the men involved.
Detective Chief Superintendent Gary Flannigan, of the Specialist Crime Division, said: "The investigation was large-scale and complex - this was a fatal shooting on the streets of the capital city, something which is thankfully a very rare event but which resulted in one man being murdered.
"Those involved set out with the intention of causing serious harm and engaged in a course of conduct which put members of the public at risk through the discharge of a high-powered weapon, their violent behaviour and a vehicle pursuit which showed recklessness in the extreme.
"The span of our investigation crossed UK - from Willowbrae to London - and abroad in terms of our search for those responsible and significant witnesses and involved a number of other agencies including the National Crime Agency.
"Using a combination of highly technical methods, surveillance and eye-witness accounts, the investigation established the identities of those involved, their movements and their intentions."