Nikye Thomas was chased through Burlington Arcade and New Street Station on a busy Saturday afternoon, dropping his loaded gun before finally being taken to the ground.
The drama unfolded at around 3.10pm on June 24, when a woman phoned 999 to report a fight near the Snow Hill Station car park.
Thomas, aged 19, was seen grappling with a man over a small bag. Seconds later he pulled a handgun out and pointed it at the other man.
The man he was threatening fled the scene and Thomas made off, but firearms officers spotted him and chased him.
Dramatic footage released today showed how officers relentlessly pursued him before bringing the chase to a safe conclusion outside New Street Station.
When the gun was recovered at Burlington Arcade, five live rounds were in the magazine with another in the chamber ready to be fired.
A quantity of cannabis resin, some scales and a burner phone were also found in Thomas's bag.
In interview, Thomas initially gave false details to officers before answering 'No comment' to all questions.
Thomas, of Colindale Road, Birmingham, was jailed for five-and-a-half years at Birmingham Crown Court on September 13 for possession of a firearm with intent to cause fear of violence and possession of cannabis with intent to supply.
Detective Sergeant Sharon Owen, from the West Midlands Police Major Crime team, said: "This was a shocking and reckless act which happened in the middle of a busy Saturday afternoon at a time when the city was full of innocent people.
“Thanks to great work by CCTV operators, firearms officers, forensics and investigators, Thomas is now behind bars.
"In addition to the five rounds in the gun's magazine, one was in the chamber and ready to be fired.
"Carrying guns on our streets is completely unacceptable and this investigation could easily have become a murder investigation had he pulled the trigger.
"We are determined to take guns off the streets and arresting those who think it is acceptable."
The conviction comes after West Midlands Police launched Operation Target, which is focused on bringing serious and organised criminals to justice in the West Midlands.