30-40 Krag ammo refers to the type of ammunition designed for the 30-40 Krag rifle, which was the standard issue rifle used by the United States military at the end of the 19th century and into the early 20th century. The cartridge, also known as .30 Army or .30 Government, features a rimmed bottlenecked design and was originally developed for use in the Krag-Jørgensen rifle. It has a bullet diameter of .308 inches (7.8 mm) and utilizes smokeless powder.
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