Oh, and as far as the 'common use' thing goes, we might have a wedge in the form of the M4 for both SBRs and automatic weapons. After all, it's in common use by our very own military.
The court specifically denied this line of thinking:
"That would be a startling reading of the opinion, since it would mean that the National Firearms Acts restrictions on machineguns
(not challenged in Miller) might be unconstitutional, machineguns being useful in warfare in 1939. We think that Millers ordinary military equipment language must be read in tandem with what comes after:
- rdinarily when called for [militia] service [able-bodied] men were
expected to appear bearing arms supplied by themselves and of the kind in common use at the time. 307""
"We therefore read Miller to say only that the Second Amendment does not protect those weapons not typically possessed by
law-abiding citizens for lawful purposes, such as short-barreled shotguns."
So M4's are flat out, because they are not commonly possessed by citizens.