It took me a while to dig trough my library, but I finally found weapon which might be called "flintlock repeater": The Mortimer multi-shot pistol which uses modified Lorenzoni system.
Normal Lorenzoni pistols. Crank is used to turn the drum breech so that it can be loaded from above.
Mortimer Multi-shot: a modified Lorenzoni with 7-shot magazine. Crank is on left side of gun and not visible in this photo.
At the rear of the barrel was a drum which was rotated with external crank. The drum hand two recesses, one for ball bullet and one for powder charge. The wooden pistol grip had hopper for bullets and reservoir for loose black powder.
The Mortimer multi-shot was loaded by pointing the barrel downwards, and turning the crank once. When the drum was rotated, one bullet would drop from the hopper into bullet recess at quarter-turn, and drop from recess into breech at half-turn later. In a similar way, black powder poured into the powder recess at half-turn, and at full-turn the powder recess was behind the breech, forming the firing chamber.
Mortimer multi-shot was dangerous weapon for the user, since there was a possibility that propellant gases would flow around the drum and ignite powered reservoir.
The pistol fired 12.7 mm lead balls at 135 m/s muzzle velocity. The grip held bullets and loose powder for 7 shots.
Source: Smith, Graham - Military Small Arms (1994)
