You can't conclude that Roberts isn't a "conservative" on the basis of this ruling. After all, Scalia himself wrote in Heller that the individual gun right is subject to reasonable regulation (and this case doesn't even involve a ban on any type or classification of gun).
There is a case, though, that will provide a tell. The SCOTUS is, once again, being asked this term to insinuate itself into the political process by ruling on two separate gerrymandering complaints (one brought by Democrats, one by Republicans). The Court should hold that such disputes are not justiciable, that the states are afforded the authority by the Constitution to decide how to elect their representatives to Congress, and that any restrictions on gerrymandering are to imposed by act of Congress, not the courts. The Constitution is perfectly clear that Congress has the power to restrict gerrymandering.
If Roberts holds that such inherently political disputes are justiciable, then I'll agree with folks that the man ain't conservative.
