Match "hollow-points" such as the Sierra MatchKing or Hornady BTHP Match bullets are NOT designed to "open up and expand." They are strictly designed to fly accurately so that the holes they put in paper are close together. The open tip is not at all designed like a standard hollow-point needs to be to expand. The only reason for the hollow tip is because the lead core is inserted base-first into the jacket (allowing for a very uniform bullet base, which is necessary for accuracy), and so there's no way to completely close the jacket at the tip without affecting accuracy.
Now, to answer Maverick's question, these match bullets will FRAGMENT at close ranges (out to 200m or so) for the same reason M193, M855, or the 68-77gr .223 match bullets do: the jackets are thin, and can't hold together under the friction they are subjected to when the bullet yaws.
147-150gr FMJ bullets don't fragment (with the exception of now-defunct West German "DAG" ammo that used very thin jackets) at any range, so their wound profile is limited to a channel that, at its widest point, is only as wide as the bullet is long. The 168gr ammo acts exactly the same way once it has lost enough velocity that it will no longer fragment, which is probably at ranges 200m and beyond.
-Troy