277 SIG Fury: An Inside Look

by
posted on January 20, 2020
** When you buy products through the links on our site, we may earn a commission that supports NRA's mission to protect, preserve and defend the Second Amendment. **
In developing a system for entry into the U.S. Military's Next-Generation Squad Weapons trials, SIG Sauer has spent much R&D time, energy and money into optimizing the round required for these future firearms. One specification required for NGSW entrants was the use of a 6.8 mm round, and SIG's answer was a specially designed hybrid case for the bullet. Commercially, this unique cartridge design came to be known as the 277 SIG Fury.

To meet the velocity and energy needs of the U.S. Military while retaining a 6.8 mm round, it was necessary to increase the pressures used in propelling the round from the barrel. While the 5.56 NATO runs at pressures of around 55,000 PSI, the new 277 SIG Fury required chamber pressures around 80,000 PSI.

For guns and cartridges to withstand these increased pressures without failing, a revolutionary case design was created. The 277 SIG Fury has three components in the cartridge case, all of which work together to create more capable ammunition than has ever been seen before. 

Watch American Rifleman's First Look video on the unique design of the 277 SIG Fury above.

Latest

Building an AR-15 lower receiver
Building an AR-15 lower receiver

Review: Assembling an AR-15 Lower Receiver

Building a high-quality AR-15 starts with selecting appropriate components.

Suppressors Deregulated in South Dakota

In a move anticipating a further reduction of restrictions, South Dakota has removed the law requiring the Federal stamp.

The Pursuit Of Increased Muzzle Velocity Comes With A Price

The quest to make our firearms’ projectiles move downrange at ever higher velocities cuts across multiple shooting pursuits and predates anyone alive today.

Review: Springfield Armory Hellcat .380 Pistol

Springfield Armory just released its popular Hellcat double-stack, striker-fired pistol in .380 ACP, and it might be an ideal option for armed citizens looking for a soft-shooting handgun for concealed carry.

New for 2026: Langdon Tactical Technology Beretta Cheetah Pistol

Beretta's .32 ACP Cheetah gets the Langdon Tactical upgrade package.

The Armed Citizen® Feb. 16, 2026

Read today's "The Armed Citizen" entry for real stories of law-abiding citizens, past and present, who used their firearms to save lives.

Interests



Get the best of American Rifleman delivered to your inbox.