The revolver is a Mateba Semi-automatic revolver. It's a first model chambered in 38/.357 magnum. The grips are made from French Walnut. As you can see, it fires from the bottom six o/clock position. The upper portion of the gun cycles so quickly because it only has to advance to the next chamber and doesn't have to slide to the rear to accept a long cartridge. It's impossible to see when someone fires it. It has removable barrels with an internal barrel and external shroud. The second models don't use a spanner wrench. The nut for the shroud is actually a compensator.
Check the Serenity poster on my profile page.
Nuts. You just reminded me that the Sarah Conner Chronicles got canceled.