Aaron Melville, 21, was arrested on December 1 last year after officers raided a house on Walker Brow and found a number of items including several homemade weapons, a revolver which was found to be a modified revolver, a dismantled handgun, a number of rounds of ammunition in the process of being converted from blank firing to illegal ammunition, and a number of tools.
Officers also found a delivery note that showed Melville had ordered three Retay blank firing pistol replicas on September 11 2020.
Detectives later discovered that Melville had ordered 25 firearms - two of which were found in the address by officers - and another one that had been found converted in January 2020 with his DNA on.
Melville, of Walker Brow, was jailed for five years and seven months at Manchester Crown Square on Tuesday (September 28) after pleading guilty to possession of a firearm and ammunition.
Detective Constable Christopher Chinnery, from Greater Manchester Police's Serious and Organised Crime Group, said: "Melville had a clear set-up and a keen interest in firearms, which could have led to some devastating consequences.
"A lot of the work we're doing to tackle firearms aren't always visible but the raid on Melville's home is an example of us acting on intelligence and taking another dangerous criminal off the streets of Greater Manchester.
"Converting Retay guns into live-firing lethal firearms is a national issue and one we're absolutely committed to tackling in Greater Manchester and Melville is one of many we're bringing to justice for it."