William Dempsey, 29, from Westwood Gardens, Paisley - a private serving with the 5th Battalion the Royal Regiment Of Scotland - was sentenced to eight years.
He was one of four plotters who appeared at Liverpool Crown Court yesterday for sentence following a trial earlier this month.
Barry Kelly, 34, from Dalquharn Avenue, Darvel, Ayrshire, was given nine years, while Craig Colquhoun, 28, of Murray Place, Barrhead, was jailed for seven years.
Another man, James Ashdown, 32, of no fixed abode was also given eight years.
Detective Chief Inspector Simon Taylor, who led British Transport Police's investigation, said: "These four clearly intended to put illegal firearms on to the streets of Scotland."
The court had heard police were alerted to the conspiracy in August last year when Dempsey was at Carlisle rail station.
He asked two cleaners to look after bags he was carrying because he believed he was being followed.
Demspey left the station and the cleaners took the bags to the British Transport Police (BTP) office where they were found to contain an Uzi sub-machine gun with silencer, a sawn-off shotgun, a hand gun and a variety of ammunition.
BTP circulated Demspey's details to colleagues in Cumbria and he was traced to a rail viaduct in Carlisle and arrested.
Officers discovered Dempsey was in the Army and a search at his barracks in Canterbury uncovered a handgun-shaped crossbow and several metal tipped arrows. A search of his parents' home in Paisley uncovered a small block of cannabis resin in his bedroom.
However, no weapons were missing from the armoury, leading officers to suspect he was part of a supply chain moving firearms around the country.
Further investigation revealed links to Colquhoun and Kelly. On August 16 last year, Colquhoun was captured on CCTV at the Royal Bank Of Scotland, Paisley, paying £3500 into Dempsey's account.
Officers arrested Kelly, Colquhoun and Ashdown and during the arrests found £20,000 hidden in Kelly's house.
Earlier this month, Kelly and Colquhoun were found guilty of firearms offences, while Dempsey and Ashdown pleaded guilty.
Ashdown was also given three years for possession of drugs with intent to supply.