First, don’t force the auger. It’s designed to handle tough soil, but hitting rocks could damage the tool. If you encounter a hard patch or rock, stop drilling, remove the auger from the hole, and try to remove the obstruction before continuing. If there is no obstruction, just hard ground, try leaning the auger at a slight angle while drilling. This will often get the teeth to once again bite into the hard ground. Our heavy duty augers have a pilot auger that is a huge asset for these types of soils.