Heller was not the definitive Second Amendment ruling.

 Today, again at The Federalist Mark Overstreet has a very good article entitled Ruling Against California's 'Assault Weapon' Ban Offers Supreme Court A Chance To Fix Heller, that describes the state of play in the continuing fight to preserve the Second Amendment.

California will appeal Judge Benitez’s decision to the activist Ninth Circuit Court of Appeals, which has often issued adverse Second Amendment rulings, and might be expected to do so in this instance. Already, however, an earlier decision overturning the gun ban, by the U.S. District Court for the Central District of California, in Rupp v. Becerra, is pending at the Ninth Circuit. Yet another decision from Judge Benitez, Duncan v. Becerra, overturning California’s ban on standard-capacity ammunition magazines common to AR-15s, comparable rifles, and countless semi-automatic pistols, has been upheld by a three-judge panel at the Ninth Circuit and is pending en banc review.

Of course, all of these cases could end up being appealed to the Supreme Court, but the court has already refused to take several cases challenging “assault weapon” bans in other states. Assuming the court took one or more of the California cases, however, it would have the opportunity to correct errors it made in Heller, which otherwise could be the basis for prohibiting defensive arms of the future.

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On the other hand, Heller mischaracterized the Supreme Court’s decision in U.S. v. Miller (1939), to say that the right to arms is limited to arms that are already “in common use,” a notion that Justice Stephen Breyer correctly ridiculed in his dissent.

It is true that U.S. v. Miller observed that “when called for service [militia members] were expected to appear bearing arms supplied by themselves and of the kind in common use at the time.” But far more importantly, it recognized that the right to arms includes arms that “have some reasonable relationship to the preservation or efficiency of a well regulated militia,” such as those that are “part of the ordinary military equipment” and any others the use of which “could contribute to the common defense.”

In support of that, the court cited the decision of the Tennessee Supreme Court in Aymette v. State (1840), that the right includes arms “such as are usually employed in civilized warfare, and that constitute the ordinary military equipment. If the citizens have these arms in their hands, they are prepared in the best possible manner to repel any encroachments upon their rights by those in authority.”

But, of course, the real question is why the Supreme Court adopted the "in common use" test? Because, the the idea that only those weapons in common use are protected under the Second Amendment, then this ruling could be used as a way to prevent improvements to arms. Imagine that Heller had been in place say when Colt invented the revolver. Might we still be using single shot muzzle loading pistols?  For that matter, would we still be using muskets?

You need to read all of Overstreet's article.  Ultimately, it must be realized that Heller was a step on the road back to achieving the fullest meaning of the Second Amendment. If we truly understand the Second Amendment, civilians would be allowed to own and posses, including training with, the personal defensive armaments carried by our soldiers at the time.  Too many people view Heller as THE definitive ruling.  It is not.