The cartridge weighs 5.3 grams and measures three millimeters wide and 11 millimeters long, with a muzzle velocity of 650 feet per second. As Frank Barnes in Cartridges of the World says “It remains potentially lethal and claims were made that it could penetrate 1 ½” of pine”. As for its general usefulness, he goes on to say that “it might do to dispatch a trapped mouse or eliminate an overly aggressive cockroach”. The cartridge was not well accepted as the size made it difficult to handle and load. The round had accuracy issues as the technology of the time was incapable of rifling such a small diameter bore, resulting in no spin on the bullet. These Kolibri pistols were produced in a semi-automatic and single shot versions until 1925 and it is rumored that less than one hundred pistols were made. Not only is it the smallest center-fire pistol produced, it is one of the rarest and sought by collectors worldwide.