The cartridge was designed as an improvement to the .50 BMG cartridge, a common machine gun and rifle cartridge. It is a wildcatted .50 BMG case, shortened to from its original length of 3.91 inches (99 mm) and necked down to accept a .416 caliber, projectile; however, the case dimensions are proprietary. Because the two cartridges, the .50 BMG and .416 Barrett, have identical base dimensions, all that is needed to convert a rifle to use one or the other cartridge is a relatively quick barrel swap.