*This is not legal advice*
I spoke with an officer at the Maryland State Police Licensing Division and I was asking about going to Thurmont Conservation and Sportsmens Club in Thurmont, MD from Virginia to practice with my new Stag 3G Rifle, which is a banned rifle as of Oct 2013 in Maryland.
She told me that all new restrictions are only for Maryland residents.
As long as you are legally entitled to possess the "Maryland banned rifle" in your home State, then you are allowed to take it to a legal shooting range in Maryland for competition or practice. When transporting the rifle, it must be unloaded, ammunition separate and in the trunk or rear of the vehicle. Also, high capacity magazines are allowed for non-residents, but you just can't sell or give one to a Maryland resident. FYI, Maryland residents appear to be able to drive to another State and buy high capacity magazines legally. (During my research I found this in the Maryland Police documents.)
Also, you can stop for lunch/dinner and gas without violating the law. I didn't ask about staying overnight since I live in the area.
And, of course, Title 18 allows you to drive through the State with your legal rifles/mags, subject to the well-known Title 18 requirements.
FYI, for Handguns same rules are in place, but since they didn't ban any handguns (Only AR-style pistols), then the law didn't affect handguns. High Capacity mags are allowed for competition and practice.
I am glad because it means I can shoot my new Stag 3G as soon as I get it. I have a Burris 1-5x24 on order, due in late April to go on it for 3gun.
Thanks,
Cody