Probably the least known of the early automatic pistol designs is the Mannlicher. The design went through several stages, starting as blow-forward action (the short-lived 1894 model), followed by a fixed barrel and finally a delayed blowback in several variations. This process began in 1896 and continued until around 1904 or 1905. Like many of its contemporaries, the Mannlicher was offered in both pistol and carbine configurations (either as a pistol with detachable stock or long-barrel carbine with a permanent stock).
While there are some minor differences in the different variations of Mannlicher pistols, they are all very similar to the original 1896 model. The pistol uses a short recoil type of action with a falling block to lock. The bolt and barrel travel backwards together under recoil for a short distance, until the bolt is cammed down and out of its locked position and continues backwards to eject from inertia. The magazine is comparable to a C96 Mauser magazine, but with with the follower guide on the opposite side.
German (click to download in PDF format):
Photos of a Mannlicher 1910 (click to download high-resolution copies)
Manowar’s Hungarian Weapons has articles on half a dozen Mannlicher pistol variants (look under “Monarchy 1867-1918”, and then “Mannlicher pistols”)