I live in Maryland and I am interested in removing the stock on my Remington 870 and turning it into a pistol-grip only shotgun. It currently has a 18 1/2 inch barrel. Is this configuration illegal/classified as an assault weapon or handgun? Now I don't want to hear any of that banter about how pistol grip shotguns are of no tactical/practical value. I just want to make sure that I don't go to jail for having one.