Sweden's Lundberg leads in Austria
Mikael Lundberg of Sweden drives from the 15th tee in Northern Ireland on July 1, 2012 - by Peter Muhly
Lundberg, targeting a first European Tour title in six years, had shared the overnight lead with England's Adam Gee, who carded a 73 to slip to sixth, five shots off the pace.
Lee Slattery is lying second, one shot off the top, with Fabrizio Zanotti a further shot away in third.
Lundberg, targeting his third title, said: "I hit a lot of good shots early on and managed to make some putts, so that got my confidence up.
"I've been doing some great work with my new coach, Neil Jordan, over the last few weeks, and my game is feeling a lot more solid as a result. So whilst I didn't maybe expect to play this well here, it's not a complete shock to me either."
The 40-year-old's previous wins came in the Russian Open in 2005 and 2008 but he hasn't had a top ten finish in nearly two years.
Slattery carded an eagle, five birdies and one bogey in his impressive 66.
"It was great," said Slattery, whose only European Tour win came in Spain three years ago.
"I got off to a decent start again today, and I was off and running. I made some good up and downs at important times, which kept the momentum going.
"It's a tricky course, there are potential disasters on every hole so you definitely can't afford to get ahead of yourself.
"It's quite old school golf where you’ve got to control your ball and put it in the right places. That suits me, so I'm enjoying it."
The best recovery came from Australian Brett Rumford, who played his first four holes in five over par but the remaining 14 in seven under to return a second round of 70 and finish one under par.