Unfortunately, it depends on where you will be traveling to and what kind of gun you are looking to travel with. There is Interstate Transport (between states), Intrastate Transport (within Maryland).
During Interstate Transport, when you cross state lines, the gun has to be unloaded, locked in a case, in separate parts of the car from the ammunition. When traveling Interstate with your gun, you may stop for food, lodging, or temporary domicile of at least one day. While you are in a state, you must adhere to that state’s gun laws. Check the state’s gun laws before you travel.
During Intrastate Transport, when traveling within Maryland, it depends on what kind of gun you are traveling with. For a Long Gun or Rifle, you should keep it separate from ammunition with the magazines unloaded. For a HandGun, you should keep it separate from ammunition with the magazines unloaded, but you can only travel to and from your place of business, to and from a gun shop, to and from a gunsmith, to and from a formal or informal shooting event, or to and from dog obedience training. You may not stop for any reason.