my guess is that a driver would be the only way to go in pure sand. You are talking about a hydraulic driver, correct? I know that when we were drilling in soft dirt on my place, the sand / dirt just fell right back into the hole as soon as the auger was lifted! Thankfully we only had about 25 sandy holes, as we were able to used a manual post hole digger to clean the holes out. The other 430 holes were pretty much good hard clay or rock, love how that rock bit just dug right through the rocks! We rented a skidsteer unit, was very much faster than my tractor driven digger.