Corey Mitchell Gesler, of Norwood, was released with time served on Tuesday

Corey Mitchell Gesler pleaded guilty to possessing a shortened firearm, possess ammunition when not the holder of the appropriate firearm licence, possess a firearm when not the holder of a firearm licence of the appropriate category and possess a controlled drug.

Police found the rifle in a backpack, 82 rounds of .22 caliber ammunition and a small amount of the drug ice during a search at Gesler's Norwood address on July 23.

During sentencing in the Launceston Magistrates Court on Tuesday, defence lawyer Patrick O'Halloran said his client had the gun in his possession for no more than two days.

Mr O'Halloran said firearm offending was out of character for Gesler, who'd been in full-time employment for majority of this year and was trying to be a law abiding citizen.

Gelser's acquaintance left the rifle at his Norwood address the night before the search warrant was executed, the court was told.

A forensic analysis of the gun found Gesler's fingerprint on the trigger.

Mr O'Halloran said during previous stints in jail Gesler was not a model inmate, but he had been for the past two months, even taking on a job as wardsman.

Magistrate Ken Stanton said he took into accountant Gesler's personal circumstances and the fact he'd been a model detainee since July.

"Not withstanding your history of violence, rehabilitation isn't lost on you," Mr Stanton said.

"You're a person who is clearly engaging ... you're a charismatic young man who could make a positive contribution."

Gesler was sentenced to two months' jail, backdated to July 23.

He was immediately released from custody.

"I really don't want you to be back here, Mr Gesler," Mr Stanton said.