Say Hello to the 5 Best 9mm Guns on the Planet The 9mm Luger round will be around for many more years. Here are five of the best guns the round is used in. Here's What You Need to Remember: Originally developed in Croatia as the HS2000, the Springfield XD (“Extreme Duty”) handgun has enjoyed considerable success in the United States. The XD externally resembles a Glock, from nearby Austria, though is somewhat blockier in appearance. The standard service model features a four-inch barrel—par for the course on this list—and a double-stack magazine that holds up to sixteen rounds of 9mm Luger ammunition.