Point damage means that the gun can hit one target at a time. Lasers, which can go through everything, can hit more people, but doesn't hit two players at the same time either. So that's why laser guns are also point guns. A weapon that shoots explosive bullets, will be added to the splash damage weapons.
To add a weapon to this category have you got to go to the weapon and place that in his categories. Please do that by the following order: Weapon | (Class) Weapons | (weapon's slot) weapons | Point/Splash damage.