Abstract: A soil sample core system includes an outer cylinder having first and sec ends; a sample tube for sliding within the outer cylinder; a tip sleeve mounted to the first end of the outer cylinder; a push pipe which may be mounted to the second end of the outer cylinder to prevent the sample tube from sliding out of the second end; a tapered tip which may be selectively extended out of the tip sleeve and which may be selectively retracted into the push pipe; an end cap having a threaded bore which may be mounted to the second end of the outer cylinder in place of the push pipe; a threaded shaft threaded in the threaded bore; a piston rotatively mounted to one end of the threaded shaft for sliding within the outer cylinder; and a torque transmitting element mounted to the other end of the threaded shaft for transferring torque to thread the shaft through the threaded aperture.