6.8 - / 10 Warhistory...

: 7.0mm (.277 in), the same diameter used in the .270 Winchester.

While the 6.8 SPC was hailed as the "clear and unequivocal best performing" cartridge in some terminal ballistic studies (like the 2006 Joint Service report), it faced challenges: 6.8 / 10 WarHistory...

: Soldiers felt the standard 5.56 NATO round lacked "stopping power" and range, especially when fired from short-barreled carbines like the M4. : The project was a collaboration between Remington

: It delivers approximately 44% more energy than the 5.56mm NATO at ranges of 100–300 meters. the U.S. Army Marksmanship Unit (USAMU)

: The project was a collaboration between Remington Arms , the U.S. Army Marksmanship Unit (USAMU) , and United States Special Operations Command (SOCOM) . Technical Specifications

: Developed in the early 2000s, the cartridge was based on the .30 Remington case, necked down to accept a .277-inch bullet.