How to make weapons get picked with only USE

Whenever I walk near a weapon in Gmod I pick it up. I want to know what I have to do in Hammer to have an SMG be able to get picked up with only the USE key. (I’m using gmod)

Disable the trigger box with this function: http://wiki.garrysmod.com/page/Entity/UseTriggerBounds

[editline]22nd October 2016[/editline]

This cannot be done map-side to my knowledge as the BaseCombatWeapon will set the trigger bounds itself, initially

I don’t know how to use this, do I write it somewhere in the map’s text file, is there any entity I can put this code in to?
If this uses LUA I want you to know idk how to use that,

If you only want to do this with mapping, you could use a prop_dynamic with a world model of the weapon you want to pick up. Then you create a button around the weapon, and use a point_template to spawn the actual weapon entity where the player will be standing at pressing +use on the weapon. Finally make it delete the button and prop_dynamic. This will have the exact effect you’re asking for.

Otherwise you’re going to have to do some Lua.

I copy pasted “Entity:UseTriggerBounds( boolean enable, number bloat=0 )” from the linked page into a .lua file and I keep getting that error. I don’t have any experience but can you guys help me with the typing? (also the .lua file is named mop)

I would use the method Rory described as it will work with every Source game and not require hardcoded MapID entities in the code.

There’s just one problem with this, the gun can only spawn in one place on the map, is there any way I can make it spawn next to the player who pressed the button?