Forum:Weapon drops of new level

Does anyone know if having an earlier level of a weapon will prevent a newer version, or as good of a version, of a weapon from dropping? Ive noticed that if I get a drop of the same weapon I already have, its almost always worse (assuming the same level). Im curious if I have say a penetrator sniper from level 18, if having that will prevent me from getting a new one, or if I get a new one if it will be worse because I already have one in my inventory. Anyone know if the game mechanics do anything there?