Special Forces-designed AR-15 cartridge offering dramatically better terminal performance than 5.56mm in short barrels.
Type: Rifle
Introduced: 2004, United States
Parent case: .30 Remington
Standardization: SAAMI
Bullet diameter: 0.277" (7.03 mm)
Case length: 1.686" (42.82 mm)
Overall length: 2.315" (58.8 mm)
Max pressure: 55,000 PSI
Rim type: Rimless
Primer: Small Rifle
Typical twist rate: 1:11 to 1:12
Muzzle velocity: 2450–2900 fps
Muzzle energy: 1130–1575 ft-lbs
Effective range: 500 yd
Common bullet weights: 85, 110, 115, 120 gr
Primary use: Military, Hunting, Self-Defense
Production status: Active
Also known as: 6.8 SPC · 6.8x43mm
History: Developed by U.S. Army Special Forces and Remington after perceived terminal performance issues with 5.56mm in short-barreled M4s. Uses the same bolt as 5.56mm but a larger case and heavier bullet. Never adopted as a standard military cartridge.
Notable firearms: Barrett REC7, Ruger American Rifle, LWRC Six8
Military use: {"country":"U.S. Special Operations","years":""}
Similar cartridges: .277 Fury, .270 Winchester, 6.5mm Grendel