Claxton stands at 12-under-par 132, which established a new 36-record. Omar Uresti set the old mark of 134 in 2002 and Stan Utley matched that total the following year.
Jon Mills carded his second 68 of the week and is tied for second with Roland Thatcher (67) at 8-under-par 136.
Matt Hansen posted an 8-under 64 Friday to tie the course record on the Upper Course at Peek'n Peak Resort. The 64 moved Hansen into fourth place at minus-7.
Claxton, playing in the first group out Friday morning, had two solid stretches of golf during his round. He opened with a birdie on the second and made it two straight as he birdied No. 3.
After a par on four, Claxton birdied the par-4 fifth to get to minus-9. He parred his next five holes around the turn.
Claxton ran off three straight birdies from the 11th to get to 12-under. However, the key to his bogey-free round was the par saves he made at 15 and 16.
He got up and down from a bunker over the 15th green. At 16, his drive stopped under the lip of a bunker and he was forced to pitch out. Claxton knocked his third to 12 feet and made that putt for par.
'I hit a nice sand shot to about 6 feet and made a nice par-putt,' Claxton said of the 15th. 'Then I hit my worst tee shot of the tournament on No. 16 in the lip of the bunker and had to chip out. I managed to get it to about 12 feet and made par. Those things keep the round going and keep momentum going.'
Claxton, who won earlier this year at the Melwood Prince Georges County Open, had a simple explanation for his good scores.
'I'm driving the ball well. I'm hitting my irons well and I'm finally getting my putts to fall,' he stated. 'I guess that's a pretty good combination.'
Keoke Cotner (67), Joe Daley (70), Chris Anderson (68) and Michael Sims (68) are tied for fifth place at 6-under-par 138.
Michael Letzig, who shared the lead after round one, struggled to a 1-over 73. He is tied for ninth at minus-5 with Brian Quackenbush, David Mathis, Bryn Parry, Tjaart van der Walt, Scott Gardiner, Kelly Grunewald and Chris Smith.
The cut line fell at 1-under-par 143 with 61 players making it to the weekend.