Nope it is legal and therefore I am exercising my rights. Following is quote from AG
7. What requirements exist for citizens while transporting long guns to and from
various destinations?
While there may be federal laws that control the transportation of firearms on airplanes and trains, the only Maryland law I have found that relates to this matter with respect to long guns is NR
You still leave yourself open to things like "disturbing the peace". They can say they didn't charge you with a firearm violation, and still be within the letter of the law. All they need is a "mad man with shotgun on a motorcycle" call.