Engineering:2.34mm rimfire
From HandWiki
2.34 mm rimfire is the type of ammunition used in the Swiss mini gun revolver. It is the smallest caliber in the world used in the smallest usable gun in the world according to SwissMiniGun and Guinness World Records.[1]
References
- ↑ "Guinness World Record". Archived from the original on July 27, 2011. https://web.archive.org/web/20110727202224/http://www.swissminigun.ch/img/certificat.gif. Retrieved December 26, 2014.