glua_strip_empty_swep

function SWEP:PrimaryAttack()
    -- anything here will be executed on both, server and client realms
    self:TakePrimaryAmmo(1)

    if CLIENT then return end -- stop anything past this line from executing on the client realm
    if self:Clip1() <= 0 then
        self.Owner:StripWeapon("weapon_ttt_dummy")
    end
end