When the target of a range weapon is adjacent to the character, it counts as point blank range. This makes no difference to the attack or defence except when the weapon has a long barrel (e.g. a rifle) or is similarly cumbersome (e.g. a long bow).
The problem with using a sizeable range weapon against an adjacent target is that it is easy for the opponent to deflect the weapon. Plus, due to the close range, the user has to move their weapon a relatively large amount to keep the weapon aimed as the target moves.
All two-handed range weapons grant the target a 1d6+0 situation bonus at point blank range unless they are specifically a short-barrelled weapon such as as a carbine or coach gun.