sustain four volleys (100 rounds) per minute in ordinary operation and reach five volleys (125 rounds) per minute during emergencies. The rapidity of discharge of each individual volley (25 rounds) was controlled by the gunner's action on a small manual crank on the right side of the breech. The weapon's 25 barrels were not discharged all at once, but in rapid succession. Because it was so heavy (1,500 lbs), the Reffye mitrailleuse did not recoil during firing and thus did not need to be re-sighted on its target after each volley. This essential absence of recoil during firings was promoted by Reffye as a considerable advantage over conventional field artillery. Each regular battery of Reffye mitrailleuses lined up six guns firing together, more or less side by side. The Reffye mitrailleuse used a 13 mm (.512 inch) centerfire cartridge, designed by Gaupillat, which represented the state of the art in ammunition design at the time. It was rather similar to an elongated modern shotgun shell: centerfire with a rimmed brass head and a dark blue hardened cardboard body. The , 13 mm (0.512 inch) patched bullet was propelled by 185 grains (12 grams) of compressed black powder at a muzzle velocity of , three and a half times more powerful than Chassepot or Dreyse rifle ammunition. This was, by far, the most potent rifle caliber ammunition in existence at the time. The Montigny and Reffye mitrailleuse systems were not designed to function with paper cartridges such as the 11 mm Chassepot combustible paper cartridge. The 13 mm centerfire Reffye mitrailleuse cartridges were loaded into interchangeable steel breech blocks, unlike the Montigny mitrailleuse, whose ammunition was held by the cartridge base in plates. When firing the mitrailleuse, three breech blocks were kept in continuous use: one being fired, one being pressed down on the extractor and one being loaded from a single pre-packaged 25-round box. Adjusting the elevation of the mitrailleuse in accordance to the distance to the designated target was performed with an elevating screw identical to that on a regular artillery piece. The mitrailleuse's barrel could also be moved sideways while firing, to the right and left, in order to adjust for range and provide lateral sweeping fire if needed. The lateral sweep was narrow, however, thus most effective at far distances only. The weapon's field of fire was so narrow that Prussian soldiers were often hit by several