A man was caught with eight guns after armed police swooped on him in a city centre street.
Paul Duncan was held after his Mazda 6 car was stopped on August 21 this year.
Officers found a self-loading pistol hidden in a sock in the motor as well as "homemade" ammunition during the search in Glasgow's Sauchiehall Street.
Police went on to search the home the 55 year-old first offender shared with his wife in Erskine, Renfrewshire.
Prosecutor Angela Gray told the High Court in Glasgow how a black suitcase was found in a lock-up garage there.
It contained six more converted pistols, a revolver as well as several further packages of ammunition.
Miss Gray: "He was interviewed, but declined to answers questions put to him."
The hearing was told the guns had originally been designed to fire blank cartridges, but had been converted.
The advocate depute: "The pistols...and one revolver..were tested and it was confirmed they had enough energy to be considered lethal barrelled weapons."
Duncan on Thursday pled guilty to nine firearms charges including possession of the guns and ammunition.
John Scullion QC, defending, said Duncan had got involved after falling on "hard times".
Lord Armstrong remanded him in custody pending sentencing next month.
Detective Inspector Martin McGhee, of Police Scotland’s Specialist Crime Division, said: "Police Scotland welcomes the conviction of Paul Duncan.
"There is absolutely no place for illegal firearms in our communities and we will do everything we can to remove them and bring those responsible for such criminality before the courts.
"I would urge anyone who has information about the criminal use of firearms to contact Police Scotland on 101. Your information can be vital in helping us protect communities and keep people safe and will be treated with the utmost confidence."
