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

Ukraine Operators
Ukraine Operators

Ukraine Operators Use Drone Round to Defeat UAS

Ukrainian operators recently tested and defeated drones with the Drone Round—a purpose-built cartridge that requires no firearm modifications, no new equipment and no additional training.

From The Counter: The Gun Store Prime Directive

When visiting a firearm retailer, know when it’s appropriate to interject, and when you should keep quiet.

Red-Dot Occlusion Training: A Performance-Booster for You & Your Optic-Equipped Handgun

Red-dot occlusion is a passive technique that shooters can use to remain target-focused, thereby speeding up their performance with optic-equipped handguns.

New for 2026: Dead Air Nomad Ti Over-The-Barrel (OTB) Suppressor

The Dead Air Silencers Nomad Ti OTB is designed to be a compact and lightweight suppressor for the backcountry hunter.

I Carry: Diamondback SDR in a Galco Hornet Holster

For our latest "I Carry" episode above, we paired the six-round Diamondback SDR DA/SA snubnose revolver with a simple leather holster from Galco, along with one of the latest EDC flashlights from Streamlight.

The Armed Citizen® May 8, 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.