.277 Fury (6.8x51mm Common Cartridge)
The Army's big bet — historically significant already, but for civilians it's early days: limited loads, SIG-centric guns, and a two-tier pressure story worth understanding.
Family
Rifle
Introduced
2019
Origin
SIG Sauer for the US Army NGSW program, USA
Military
6.8x51mm Common Cartridge (US Army XM7 rifle and XM250 automatic rifle)
History
SIG Sauer developed the .277 Fury for the Army's Next Generation Squad Weapon program, using a hybrid steel-head case to run unusually high pressures from a short barrel. The Army selected it in 2022 with the XM7 rifle and XM250 automatic rifle, the first new US service rifle cartridge in decades. Civilian availability exists through SIG's Cross bolt rifle and MCX Spear, though the ecosystem is young.
What it's used for
Iconic platforms
SIG MCX Spear and Cross rifle, and the Army's XM7 and XM250.
Common load types
Full-pressure hybrid-case loads and conventional-brass loads at standard pressures, in hunting and FMJ types.
Reference only — not loading data, not ballistics advice, and KitID links to no ammunition sellers. Know your local law before you buy anything that goes bang.