6 Mm XC
6mm XC (also known as 6XC) is a rifle cartridge, similar to the 6x47mm Swiss Match, that was developed specifically for NRA High Power match shooting by 11-time NRA High Power National Champion David Tubb. It is touted as being one of the most accurate long-range 6 mm rounds in the world that is designed for repeating rifles.
Originally, the case for this wildcat cartridge had to be formed from .22-250 brass, but it is now commercially available.
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