A reaming shell the inside wall of which is tapered and into which a split-ring core lifter may be fitted. also called bevel-wall core shell, taper-wall core shell. b.h. ahlr. commonly used for blasthole and/or borehole. b. h. bit. 1. a noncoring or blasthole bit. 2. a cdda standard-size noncoring bit having a set outside diameter of 1% inches. normally referred to as a 1%-b. h. bit.
