The 47-year-old has garnered 30 medals in nine Games since making his debut in 1980 in Arnhem, the Netherlands. In this edition, he has only collected silver in his four scheduled events.
But he refound his gold-winning aim at the Royal Artillery Barracks, firing 10s all the way from his third shot to the end of the competition to successfully defend the title he won four years ago in Beijing.
His 100.9 points was the highest of the session and left him with a total of 1,255.9. Doron Shaziri, of Israel, a silver medalist in Beijing and bronze at Athens in 2004, was second, with Dong Cheo of China in third.
Dong had previously picked up gold in the men's 10m air rifle standing SH1.
Jacobsson, a wheelchair user and paralysed since birth, celebrated to loud cheers from Swedish fans in the crowd and said he was delighted with yet another win.
"It was amazing. I didn't really believe that I could do it but it was the power to win. It's been tough, for the last four months I wasn't shooting my best but I did it," he said.