Gunman Uzair Shahid and accomplice Toyub Ali are both now facing lengthy prison terms after being convicted over the shooting in Walsall in 2019.
Both men had denied being at Katz Kutz hair salon when Tehmoor Hussain was shot but jurors did not believe them and today found Shahid guilty of attempted murder.
Shahid, 20, was also convicted of possession of a firearm with intent to endanger life while his co-accused, 19-year-old Toyub Ali, was found guilty of possessing a firearm with intent to cause fear or violence.
Both men were warned by the judge to expect substantial jail terms when they are sentenced at Wolverhampton Crown Court in April.
Mr Hussain, the 24-year-old target of the attack, was left with serious stomach injuries when Shahid fired a sawn-off shotgun at him during a row relating to a car which had been damaged in a crash.
The trial was told how Mr Hussain was sat in the barber's chair at Katz Kutz in Wolverhampton Road, Birchills, when the two men entered at around 5pm on May 29, 2019.
Shahid and Ali accused Mr Hussain of owing them money over a crash in Chuckery.
Mr Hussain had been in a Toyota when it was involved in a crash with a Renault, which Ali was a passenger in, prosecutor Mr Russell Pyne said.
The Toyota had driven off before any details were exchanged and Ali and Shahid had arrived at the barberhop to confront Mr Hussain over the incident.
"Toyub said to me 'you owe us money for the car'," Mr Hussain said while giving evidence at the two-week trial.
"I was sitting in the chair... He punched me on the back of my head on the right-hand side.
"I got off the chair and faced them. I was in shock, at which point Jeeza [Shahid] said 'Yeah, yeah watch'. Toyub was standing next to him."
After punching Mr Hussain, Shahid went to the BMW he had arrived in, pulled out a shotgun and went back to re-enter the shop via the front glass door, the trial was told.
Mr Hussain held the door shut from the inside in a bid to protect himself at which point Shahid fired, Mr Hussain "felt a warm feeling and fell to the floor".
The barber called 999 and the victim was rushed to Queen Elizabeth Hospital in Birmingham for treatment.
Both defendants claimed they either were not there at the barbershop at the time of the incident, but data from Shahid's ankle tag showed he had been in or near the BMW the gun was inside on the day of the attack.
The jury deliberated for two hours and 25 minutes before returning their verdict at Wolverhampton Crown Court on Friday afternoon.
Shahid, of Lichfield Road, Rushall, Walsall, and Ali, of no fixed abode, had denied all charges against them.
They will be sentenced at the same court on April 29.
Judge Simon Ward said: "You should both expect to receive a custodial sentence of some length – Shahid of considerable length.
"You will remain in custody until your sentencing."