I agree MD gun laws are stupid, but not sure if your description or understanding of gun laws in MD is accurate. Since you travel out of state often, the mag restriction basically is nothing to you. You may bring them in from other states, you just cannot buy them in MD. The MD AR barrel profile restriction only applies to .223 & 5.56, other calibers can legally have any profile; if that much of a barrel profile difference neuters an AR for you, I'm not sure how you are able to carry a rifle that shoots 6.5 Grendel