Alonza Barnett III threw for five touchdowns and ran for two more as visiting James Madison scored in a variety of ways in stunning North Carolina 70-50 on Saturday afternoon in Chapel Hill, N.C.Barnett finished 22-for-34 for 388 passing yards and cranked out 99 rushing yards on 13 carries.Omarion Dollison gained 125 receiving yards on three catches and Cam Ross had 107 yards on seven receptions. They both caught a TD pass.Barrett threw 11 yards to Logan Kyle for a touchdown with 4:26 left, and the extra-point kick by Noe Ruelas made it 70-44, matching the most points ever scored against North Carolina.James Madison scored on a blocked punt and an interception in the first half in a dominant performance by first-year coach Bob Chesney’s team. The teams combined for the most points in Kenan Stadium history in a game that lasted nearly four hours.North Carolina’s 616 yards were nearly matched by James Madison’s 611.The Dukes (3-0) had 418 first-half yards of offense. Combined with North Carolina’s four turnovers, James Madison was up 53-21 by halftime, marking the most points the Tar Heels had ever allowed in a first half.It was the final tune-up for North Carolina (3-1) before next week’s Atlantic Coast Conference opener at Duke. Running back Omarion Hampton picked up 139 yards on 19 carries with three touchdowns for the Tar Heels.