How many have actually read the decisions?
The ruling doesn't expand on the protection provided by the Heller ruling, it only extends it to apply to state & local law.
And Heller provides only the most basic protection against gun control. That is, it says that completely prohibiting the ownership/possession of an entire general class of firearms (handguns) commonly used in self-defense by the citizenry is unconstitutional.
In order to make Heller apply then, it would seem that 3 criteria must be met.
1. An entire general class of firearms must be involved.
2. That entire general class of firearms must be of a type commonly used in self-defense by the citizenry.
3. There must be a complete prohibition on the ownership/possession of the entire general class.
Even if we completely ignore the first two criteria it's still obvious that an AWB of the same general flavor as the one we went through in the 1990s is not going to qualify. Under that law one could still own/possess full-fledged AWs, they just had to be AW's that were manufactured/sold/imported before a certain date.
So an AWB with any grandfather provisions won't bring Heller or McDonald into play.
So let's say they don't put in the grandfather provisions?
Let's look at criterion 1.
It's not hard to make the point that AWs are not a general class of firearms in the same sense that handguns are. Handguns are any firearm regardless of caliber, capacity, primer type or action type that are designed to be easily fired with one hand.
AWs (per the AWB) are a specific subclass of magazine fed semi-automatic rifles which is a subclass of semi-automatic rifles which is a subclass of repeating rifles which is a subclass of centerfire rifles which is a subclass of rifles which is a subclass of long guns.
But let's say that all the justices have a simultaneous minor stroke that day and agree that AWs constitute a general class in the same sense that handguns are a general class.
That still leaves criterion 2.
Are AWs a class of firearms commonly used for self-defense by citizens? Not according to any statistics I've seen. Handguns and shotguns dominate the world of dedicated self/home defense firearms with firearms of opportunity (hunting/recreational guns) filling in the rest. AW's are rarely used for self-defense by citizens.
Heller isn't going to help prevent an AWB and therefore neither will McDonald.
...since AR15 in particular are commonly used in both rifle competitions and by law enforcement
Neither Heller nor McDonald so much as mention LE or competition uses. They are focused specifically on self-defense use by the citizenry.
I question whether 'may issue' is constitutional...
Heller was specifically about handguns for use in home defense. That was what the plaintiff asked for and that's what he got. There's nothing in the ruling that applies to carry outside the home.
It's a tremendous stretch to try to make Heller apply to any sort of CCW permit restrictions, even the complete absence of any legal provision for CCW.