Jacob Roger Dorloff, 21, was sentenced at the Supreme Court in Hobart yesterday.

Dorloff earlier pleaded guilty to two counts of aggravated assault, two counts of common assault, possessing an unregistered firearm and stealing.

The court heard the two four- wheel drivers were travelling separately along a road in the state's South-East last July when a woman waving a long metal bar appeared in front of them.

A gunshot rang out before the drivers saw Dorloff armed with a gun and another man armed with a machete. The court heard one of the drivers fled from his vehicle into the bush, with more gunshots fired as he ran.

Dorloff stood five metres from the windscreen of the second driver and pointed the loaded gun directly at him.

The woman threatened the driver before she and Dorloff robbed the man of his phone, keys and wallet. They then allowed him to leave. The drivers reunited some distance up the road and went to police.

Handing down his sentence yesterday, Justice David Porter said the incident continued to affect both victims.

Justice Porter said one victim now lived with sleeplessness and panic attacks, and the other had lost his passion for four-wheel driving. He said while Dorloff had been "swept up" in what others in his party were doing, his crimes were serious.

"Pointing a loaded firearm at someone is a particularly serious thing to do," Justice Porter said.

Justice Porter said rehabilitation should be given a degree of prominence given the offender's age, but said a community corrections order was not a suitable punishment given Dorloff's history of drug and alcohol abuse, criminal behaviour and mental health issues.

He sentenced Dorloff to 12 months' imprisonment with nine months suspended. Dorloff said "thank you, sir" to the judge and blew a kiss to a woman in the courtroom as he was escorted back into custody.