Jason Yendall, 30, Aaron Brannan, 23, Jason Britton, 23, carried out a £230,000 heist at the Rox jewellery shop in Glasgow’s Argyll Arcade last September.
Shoppers and staff dived for cover as the mob clutching deadly weapons bagged 21 high-end watches.
Britton was later unwittingly caught on a mobile phone photo wearing one of them leading to their downfall.
The trio – along with Alistair Oliver, 30, and Gordon McLay, 32, – also held up an RBS bank in Edinburgh stealing £20,000.
All five today returned to the High Court in Glasgow to be sentenced.
Yendall, Brannan and Britton had earlier pled guilty to being involved in both raids.
Oliver and McLay admitted taking part in the bank robbery as well as the reset of two watches taken from the Argyll Arcade.
Yendall was locked up for 12 years and nine months, Brannan got 10 and a half years years while Britton was sentenced to five years and 10 months.
Oliver was jailed for seven and a half years and McLay sentenced to six years.
The judge said told them: “This behaviour can truly be described as serious and organised criminal conduct.
“This involved planning, determination and the calculated use of violence.
“Some of you are career criminals to which such conduct comes easily.”
A number of the mob smiled and laughed as they were led handcuffed to the cells.
The court earlier heard how Yendall, Brannan and Britton were all friends from Manchester.
Oliver and McLay knew each other from living in Wallyford, East Lothian.
McLay was previously a talented chef who had worked in Harvey Nichols in the capital.
On September 23 – the day before the Argyll Arcade raid – Yendall, Brannan and Britton carried out a “dry run” of the route to and from the scene.
The next morning, the trio along with two unknown associates travelled “in convoy” from Edinburgh.
The gang stopped in Glasgow’s Queen Street close to the Argyll Arcade – which houses more than 30 jewellers and diamond merchants.
Prosecutor Sheena Fraser told the court: “Four of the men got out of the car – two carrying baseball bats, one a sledgehammer and one an axe.
“One of them was also carrying a holdall. The driver remained within the car.
“The Crown cannot say which of the men was the driver and which four attended at the arcade.”
The armed robbers – wearing balaclavas and gloves – stormed the busy mall around 1pm and immediately targeted the Rox store.
Rox sold expensive Hublot watches as well as Bell and Ross time-pieces
As some of the gang took turns to keep a look-out, others raced inside and smashed a window display.
Terrified staff and customers looked on as 21 expensive watches were tossed into bags.
One worker activated a device that saw smoke fill the arcade in a bid to “disorientate” the raiders.
Some shoppers captured the incident on their mobile phones. But, less than four minutes after arriving, the gang fled with their loot.
They jumped in a getaway car but not before one yelled: “I’ll f****** kill you all.
Oliver and McLay meantime were in a bookmakers in Wallyford hours after the raid.
They were each sporting £2,750 watches taken from the Argyll Arcade.
Miss Fraser added: “They had been given them by (Yendall, Brannan and Britton) after they returned to Edinburgh.
“They have not been recovered and were sold on by Oliver and McLay.”
The court heard a total of 19 Hublot watches and two from Bell and Ross were taken.
The value of the haul – which was never recovered – totalled £229,601. These ranged in value from £2,750 to £23,000.
The Argyll Arcade was also left with a £20,000 repair bill.
Yendall, Brannan and Britton were soon back in Scotland to rob a bank in the capital.
Oliver – who police had been keeping tabs on – was clocked by police buying four balaclavas and an axe at a B & Q store in Edinburgh.
He then arranged for the trio to stay at a friend’s flat – close to the RBS in the capital’s Tollcross that was being targeted.
Yendall, Brannan and Britton – all masked and carrying weapons – then held up the bank on October 2 after two of them jumped the counter.
They shouted: “Don’t f****** move or we’ll kill you. Give me your f****** money.”
They fled with £19,675 and eventually jumped into a waiting Ford car in which Oliver and McLay were in.
But, the vehicle was soon stopped by watching police. Cash and two axes were found in the back of the car.
Oliver, Britton and Brannan were all found with cash on them.
The gang made no comment other than McLay claiming he and Oliver had been eating in the car when three mystery men jumped in the vehicle and demanded they drive.
Brannan’s mobile was later checked as police probed the gang’s link to the Argyll Arcade theft.
On the phone was a snap of Britton wearing one of the watches.
Advocate depute Miss Fraser said: “In two of the photographs, a mirror is caught in the background and the man wearing a watch is caught in the mirror.
“He is clearly identifiable as Britton. This watch was one valued at £16,000.”
The gang all already had a criminal past. Yendall was out on the streets despite being locked up for five years in 2012 for another robbery.
The judge also today ordered that Yendall and Brannan be supervised for a further five years on his release. Oliver will be monitored for four years.