Some more information courtesy of The Illustrated Encyclopedia Of Handguns by A.B.Zhuk.
"...this well-balanced and easily handled weapon, specifically designed for smokeless cartridges, equipped the Austro-Hungarian army during the First World War. The double-action lock has a rebounding hammer, whilst the striker is a separate component in the breach. The spring-loaded ejector, mounted on a fixed yoke on the right side of the frame, operates in conjunction with an Abadie gate...An interesting feature is the lack of screws, enabling the gun to be stripped and reassembled without tools."
"Many of the revolvers made in Europe prior to 1914 featured the so-called Abadie Gate, which was perfected in Belguim and was particularly common on guns made by Nagant. The hammer disengaged when the gate was opened, allowing the cylinder to be turned by the trigger. Alternately pressing the trigger and the extractor-head caused the cylinder to revolve and fired cases to be ejected, greatly facilitating reloading."