Jeff Klauk, Nick O'Hern, Euan Walters, Vance Veazey and Adam Groom were one shot back at 5-under-par 66.
'I'm just trying to get the feel back in my golf game because I think I got too analytical about things,' said Painter. 'Six under feels good.'
Painter played the back side first and tallied his first birdie of the day at the par-4 13th. He found trouble with a bogey at the par-3 15th but recovered with back-to-back birdies from the 16th to move to minus-2.
The Australian, whose lone Nationwide Tour victory came at the 1998 Ozarks Open, added a birdie at the par-5 first before stumbling to a bogey at the very next hole.
Painter countered with a birdie at the third, however, and reached 4 under with a birdie at the par-4 sixth.
The 38-year-old closed his round in fine fashion with an eagle at the par-5 ninth to secure the opening-round lead.
'It was one of those you don't plan on making,' Painter said of his eagle putt. 'But in the running, with six feet to go you're thinking 'this is going in.''
Klauk also started at the 10th and collected three birdies over his first nine holes.
The 26-year-old, who captured the Preferred Health Systems Wichita Open last year, added four birdies and two bogeys on the front side for his share of second.
Nationwide Tour rookie Ryan Armour ran off eight birdies to go along with four bogeys for a round of 67.
Armour was joined by Doug Barron, James McLean, Doug LaBelle II, Wayne Grady, Bob Sowards and Jens Nilsson in a tie for seventh.
Craig Parry was one shot further back in a group at 3-under-par 68 that includes Paul Claxton and Nathan Green.
This event is co-sanctioned by the Nationwide and Australasian Tours.