ok from what i understand you cannot cut a barrel down to bellow18.5 but you can buy a manufactured one that is 12.5.could you make your own 12.5 as long as you made the whole barrel out of stock steel?if you are allowed to make your own can you make it any shorter than 12.5?please let me know.so many things I want to build but the laws frusterate me and I don't want to do anything wrong