The ten 20-year-old men were fined a total 100,000 kroner ($17,000) on Thursday and sentenced to between 160 and 190 hours of community service each, after they were found guilty of committing a hate crime.
According to the verdict, the men had become irritated that one of their hang-outs at Ingierstrand, south of Oslo, had become a place where gay men meet to have sex.
One of them set up a fake profile on Gaysir.no, Norway's leading gay website, in an attempt to get revenge.
When their victim, a man in his 50s, turned up at the parking lot where he'd agreed to meet, he was ambushed by the men, who had been hiding in the woods nearby.
They screamed "fucking gay" and "fucking faggot" at him, and unleashed several shots of a BB gun, after which he ran back towards his car, and made his escape.
Marte Svarstad Brodtkorb, the victim's lawyer, told Norway's NRK network, that her client had been severely traumatised by the attack.
"He has not been able to work and he has had several hospitalizations. His quality of life has been significantly impaired," she said.