Phil Massaro tackles the 6mm ARC, a military cartridge that's equally at home in the hunting field.

30-caliber cartridges—and you have a market for seriously fast ... For the Weatherby cartridge, you’ll see ammo available from Weatherby, Nosler and Hornady while the .300 RUM is produced by Remington ...

(Garrett Dacko/Army) The Army is one step closer to producing millions of rounds each year of its newest caliber for the service ... equipment produces 5.56 mm ammo at the Lake City Army ...