It's elemental, actually. A PT is made for the tip to expand and the base is made to hold together and give deep penetration. An AB is made to explode. The plastic tip is driven down the center of the lead and forces it apart. It opens up much faster than a PT.
“In a time of deceit telling the truth is a revolutionary act.” ― George Orwell
It's not over when you lose. It's over when you quit.
