Schniederjans hit six birdies and an eagle, with a solitary bogey, while Snedeker carded a blemish-free seven birdies as they took the clubhouse lead.
England’s Justin Rose is tied for 16th at eight under following his third-round 68, finishing with three successive birdies.
A three-over 75 from Ian Poulter saw him finish at six under and drop down the field having been third overnight.
Tiger Woods, meanwhile, slipped out of contention after a poor start.
The former world number one was nine off the lead overnight, which could have been better but for a quadruple-bogey at the 17th.
However, Woods signed for a 72 to sit at three under overall, with three bogeys on the front nine proving costly.
The American said: “I fought hard on the back nine and I just wish I had been able to put that same score on the front nine, then I would have got myself near that lead.
“A few guys are taking advantage of it, so it’s definitely gettable, it’s definitely doable. I just struggled with the green speeds being so much slower.”
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