Collision Problem

Hi all,

I am trying to create FPS melee weapon in my project .The weapon that am trying to create is a Driller.Earlier when i started doing i was facing one problem ,the weapon that is attached with the player does not have any collision so during the Weapon fire animation the weapon will pass through the wall.
I solved that problem by keeping the Weapon as different layer.But now am facing another problem.
Now On trigger enter is not working with the Weapon.What i need to do is ,during fire button press Animation will play and that time if the weapon is near the Wall i need to show Drill hole on the Wall.
For doing this i need ON tigger enter working .In this case it is not working and am not able to detect the Collision between two objects.
What exactly i need to do solve this.How can i detect the trigger?

Thanks for any help,

 

Is there a rigidbody component attached to either the wall or the weapon? If there isn't at least one rigidbody among the two objects, no collision will be registered.