Mohammed Aqeel Khan, aged 26, of Deane, Bolton, was jailed for five years after police found an antique gun hidden in his wardrobe.
Bolton Crown Court heard that Khan told officers that he came across the 117-year-old revolver while urinating in a field.
He claimed that he took it home because he was worried that it might be discovered by a child.
Khan later sent a number of pictures of himself posing with the firearm to friends and when asked why, Khan told officers he got a “bit excited” as it was the first time he had seen a gun.
On March 11, 2020, officers from Greater Manchester Police’s Xcalibre and Challenger teams executed a warrant at Khan’s home on Malton Avenue.
They discovered the revolver, originally constructed in 1903, hidden under some towels in a wardrobe, along with three bullets in a jacket pocket.
In early August 2020, a jury took less than an hour to convict Khan of possessing an illegal firearm following a two-day trial.
Khan had claimed he was waiting for a gun amnesty to be announced before contacting police about the antique gun.
Judge Timothy Stead sentenced Khan to five years in prison.
In 2019, more than 200 guns were handed in during a two-week-long firearm surrender in Greater Manchester. This included real guns, replicas and plastic imitation guns.
Among the deactivated guns handed over were an AK47, an Uzi sub-machine gun and a Bren Second World War machine gun.
Superintendent Danny Inglis said: “The firearms surrender was a great success and any gun that gets handed in is one less on the street for criminals to get their hands on. I’m really pleased with that response.
“The aim of the campaign has been to get weapons that now can’t fall into the wrong hands.”
“Some will have been held by people that had an interest in guns or they like collecting antiques.
“But if they fall into the wrong hands, for instance, if someone is burgled, criminals could end up with those weapons.
“They’re very large and intimidating weapons. If you got one of these pointed at you, you wouldn’t know it was a replica or a real firearm.
“Guns have no place in Greater Manchester and we will continue to work hard to ensure the streets of Manchester remain a safe place to be.
“The success of the surrender is as a result of continued efforts from GMP, and our partners working together to safeguard, intervene and educate at the earliest opportunity.”