Making a laser

I trying to make a laser but I just cant seem to get it working and this seems like the best way to do it but im getting tired of so much trial and error, please can someone help me
This is what iv been trying to use
[Lua]
function makelaser()

local laserp = ents.Create( "prop_physics" )
laserp:SetPos( Vector(0,0,0) )
laserp:SetModel( "models/items/combine_rifle_ammo01.mdl" )
laserp:SetKeyValue( "disableshadows", "1" )
laserp:Spawn()

local laser = ents.Create( "env_laser" )
laser:SetPos( Vector(0,0,0) )
local laserpos = laser:GetPos()+Vector( 0, 0, 7 )
laser:SetPos( laserpos )
laser:SetKeyValue( "targetname", "env_laser" )
laser:SetKeyValue( "LaserTarget", "gc_weapon" )
laser:SetKeyValue( "texture", "cable/physbeam.vmt" )
laser:SetKeyValue( "rendercolor", "255,0,0" )
laser:SetKeyValue( "renderamt", "200" )
laser:SetKeyValue( "width", "5" )
laser:SetKeyValue( "NoiseAmplitude", "1" )
laser:SetKeyValue( "damage", "0" )
laser:SetKeyValue( "dissolvetype", "2" )
laser:SetParent( laserp )
laser:Spawn()	

end
concommand.Add(“makel”, makelaser)
[/Lua]