Long guns in automobiles

[cz85cmbt]

This is a question for automobiles and carrying a backpack with a long gun in it. Maine statutes say you can carry a pistol or revolver loaded in a vehicle but do not say anything about a loaded longgun. Is it just legal to have a loaded handgun in a vehicle, or is this just a case of the author using too specific language? Furthermore there seems to be nowhere I can find in the statutes where it tells you what a ccp enables you to do legally. I am considering carrying a kel tec folding carbine in a back pack as well as in a car technically I don't care if the magazine is in the gun loaded but where does the law stand here. Give your sources.