umm Picking Up Weapons in FPS, and Zoom

How can i zoom in an fps
and how can i pick up weapons?
i currently have four empties and “weapon switch”
(each empty being a type of gun…
IE… one is AK47, one is knifing, one is grenade (no actualy grenande yet), and one is pistol)
so how can i pick up weapons in an fps suing logic bricks?
THanks you

Weapon pickup is simple. You model all of the weapons then position them how you want them, then make an int property and name it weapon (set this to the camera). Then make a controller, actuator, and a sensor to each gun. Then just make the weapons visible and in visible with the property. For instance, if Gun 1 is visible, then weapons 2 and three are invisible. Then all you have to do is change the property when you collide with a duplicate of the weapon you want to pickup.
I hope this helped!
-Fabled Face

how to i assign the empties to a certain gun?
do i have to make a bunch of empties too?
i only want four weapons being held at a time
one being main weapon
one being pistol
one being knife
and one being grenades

I wrote a tutorial on weapon switch and weapon pickup:
Maybe this will help. To assign an empty to a gun put it in front of the barrel to where the bullet will be shot from then click on the gun, hold shift and click on the empty, then let go of shift, then hold ctrl+P Then push ok on the popup screen. Now the gun is parenting the empty.