For more on the panel decision from last Summer, see here. The panel will include the Chief Judge Sidney R. Thomas, plus 10 randomly selected judges; those judges must come from either the roster of active judges, or of the senior judges who served on the panel, if they want to be eligible for the en banc (in this instance, Judge O'Scannlain and Judge Clifton). En bancs in most circuits include the entire court, but because the Ninth Circuit is so large, its en banc panels include only 11 judges.)
To the extent such things are relevant, the Ninth Circuit has 23 active judges, of whom 7 are Republican appointees and 16 (including Chief Judge Thomas) are Democratic appointees. At the same time, note that Judge Clifton, while a Republican appointee, voted against right-to-carry on the panel; and some Democratic-appointed judges on the Ninth Circuit endorsed an individual rights view of the Second Amendment even before D.C. v. Heller, though that doesn't say what they think of carrying outside the home.