The 2.7mm Kolibri Auto as compared to the .22 Long Rifle

The 2.7mm Kolibri Auto is (as far as I know) the smallest commercially available centerfire round that has ever been produced. It is the idea of Franz Pfannl, an Austrian watchmaker and was patented in 1910 and introduced in 1914. It was fired from a smooth bore Kolibri pistol.

The round is 3 millimeters at its widest point, and 11 mm from the meplat to case head.  The round headspaced on the case mouth. The bullet itself weighed 3 grains and averaged a muzzle velocity between 650 and 700 fps, creating about 3 foot pounds of energy.

There is some debate on another round called the 3mm Kolibri. It is very similar to the 2.7mm Kolibri but uses a lead bullet while the 2.7mm uses a jacketed. The 3mm is also physically larger than the 2.7mm but not by much and performance of the two are nearly identical.

The rounds and pistol were discontinued in 1938.

Kolibri, is the word for hummingbird in several languages and is where the round gets it’s name.

Given the 25 Auto develops about 73 foot pounds of energy and is less than ideal for a defensive round these Kolibri pair would be sufficient for game up to and including a rabid frog or wounded mouse. With that said, as with any firearm it can be very dangerous.







By Hunter Elliott

I spent much of my youth involved with firearms and felt the call early on to the United States Marine Corps, following in my father's and his brother's footsteps. Just after high school I enlisted and felt most at home on the rifle range, where I qualified expert with several firearms and spent some time as a rifle coach to my fellow Marines. After being honorably discharged I continued teaching firearm safety, rifle and pistol marksmanship, and began teaching metallic cartridge reloading. In the late 1990s I became a life member to the National Rifle Association and worked with the Friends of the NRA. Around that time my father and I became involved with IDPA and competed together up until he passed away. I began reviewing firearms for publications in the mid 2000s and have been fortunate to make many friends in the industry. Continuing to improve my firearms skills and knowledge is a never ending journey in which we should all be committed. I am also credited as weapons master on a few independent films.

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