There are many that would say Heller was an activist court making up law and completely overlooked precedent in Miller, in the same way the current court is overturning decades of precedent in another issue.
"United States v. Miller, 307 U. S. 174, does not limit the right to keep and bear arms to militia purposes, but rather limits the type of weapon to which the right applies to those used by the militia, i.e., those in common use for lawful purposes."