I have given my son an Ar-15 (Colt Preban) and a Custom SA 45. These are definitely "clean" but I purchased/traded for them and have no paper work. My son has a job with high clearances and feels that under the MD law there would be a real issue if he were to be pulled over and asked for ownership paperwork, etc. if he were going to/from AGC or any other range. I was advised that he should " voluntarily" register his firearms, others have told me he doesn't have to do anything. He has a great fear of possibly losing all of his firearms and more of a concern of losing his clearances and then his job. Please any other advice,recommendations to be legal in this wonderful state we live in. Thanks Help??