Churn drilling is an older form of drilling that is useful for specific types of soils and rocks. While the title refers only to churn drilling this section discusses any drill type which produces a continuous sample of soil or weakly consolidated rock. Included in this categorization is auger drilling and hollow core auger drilling. These types of drilling rely on filling an open pipe with material to be sampled. It is used to sample alluvial gold gravels, tailings piles and lateritic nickel deposits. 

A churn drill operates by rotating hollow pipe and dropping a weight or hammer on it every 10 to 15 seconds driving the pipe into the soil. Generally the pipe will have some kind of bit attached which is the same size as the pipe. Behind the bit is a section of drill pipe which has a mechanism for holding a sample of the soil. When a section of drill steel has been pounded into the ground it is pulled out section by section so that the material trapped inside the sample holder can be removed. The need to pull the complete drill string out of the ground to remove the sample makes this drilling very slow and useful for only relatively shallow holes.

Auger drilling involves turning a pipe which has auger flutes welded to it. The augur flutes act as a wood drill might and digs into the ground. If it is a hollow auger, the material is carried up into the sample holder in much the same way as a churn drill. If it is a straight auger then the material is pushed up to surface and must be bagged as it arrives. While this type of auger drilling is faster it leads to mixing of the sample and so there is less control of the location of the samples.