Issue with objects colliding

My friend made a script for a shooting target, so when an object touches the target, it'll fall down. Although, when I shot it myself. The target wouldn't go down, and I was sure the bullet had hit. I tried up close and far. At both distances, at random times, my bullet would knock it down, or just seem to not touch it. Can anyone help me with this?

Anyone have an idea?

Without seeing at least the target script, one must conclude that it's rigged so that unless the owner of the colliding object is the scripter, only some of the hits register.