Thoughts on the 9th Circuit case -- where do we go from here?
The county has 14 calendar days from the date of the ruling to move for rehearing en banc. If the county fails to move, any judge of the court, of their own volition, move for such rehearing within 21 days of the ruling. This seems to fit the grounds for such a motion, in particular conflict with other circuits and an issue of pressing national importance. A majority of the court can vote to grant.
En banc: normally, ruling are handed down by 3-judge panels. En banc in all other circuits means that all of the judges of the court take part and vote, after rehearing the matter. The 9th is so large, however (27 active-duty judges) that it has adopted a special rule. Ten judges are chosen at random, plus the chief judge (Alex Kosinski, a supporter of the 2A). For whatever it's worth, the 27 active-duty judges divide into 18 Democratic appointments and 9 Republican ones.
To complicate things, the Circuit can also vote to have a true en banc, with all 27 judges participating.
Once the en banc panel is chosen, it votes on whether to have additional briefing or argument. They almost always for for additional argument, I don't know about briefing.
If the en banc court reverses the panel ruling here, it'd make a really nice case for the Supreme Court (and maybe even if it upholds it). Big circuit split -- 7th and 9th Circuits taking a broad view of the right to bear arms outside the house, several other circuits saying "not until the Supreme Court orders us to do so." The panel decision has a great exploration of the issue, and is 77 pages long; the dissent is 40 pages, as I recall, and clearly presents the argument to the contrary. An en banc ruling would further flesh things out, with input from 11 (or 28) judges.
UPDATE: thinking it over ... en banc upholds panel decision, the result is a clear circuit split, well hashed-out, good candidate for Supreme Court. BUT since the good guys won, they cannot ask the Supreme Court to review. En banc reverses panel, less of a circuit split (there's still the Seventh Circuit, which recognized that the 2A applies outside the house, good guys lost, so they can seek review. There may also be collateral effects, in that other cases seeking cert. now or in the near future can point to the (at least temporary) split between the 7th and the 9th and the other circuits that refuse to apply Heller/McDonald outside the home.