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.277 Fury (SIG NGSW Entry)


The .277 FURY or 6.8×51mm SIG, is a centerfire rimless bottlenecked rifle cartridge announced by SIG Sauer in late 2019 as part of their NGSW program entry. It utilizes a hybrid three-piece cartridge case that has a steel case head, brass body and a locking washer that mechanically connects the two to support a chamber pressure of 80,000 psi (551.6 MPa). .277 Fury as its referred to is designed to be chambered in the SIG MCX Spear NGSW-R entry. 

.277 FURY is the second highest pressure entrant into the NGSW program, this is due to the MCX Spear having a 16 inch barrel, giving the projectile much less barrel length to get up to speed. As such the higher velocities are required to push the projectile faster with less barrel.

Each 6.8 NGSW entry cartridge has three different loads, keep in mind - while they are all designed to achieve the same task they will not all perform the same and vary entry to entry:

XM1168 - Full Metal Jacket Ball ammo. Also has a tracer variant.

XM1169 - Special Purpose Match ammo designed for long range shooting. Also has a tracer variant.

XM1170 - Special Purpose Armor Piercing ammo with a tungsten penetrator. Also has a tracer variant.

Additional ammunition types have been created as part of the trials and given unique designations, however beyond 1168, 1169 and 1170 none were requested as part of the NGSW program.

XM1185A1 - Special Purpose High Explosive-Incendiary-Armor Piercing 'Raufoss-like' load proposed for possible use by USSOCOM in sniper or marksman roles. It features a Tungsten penetrator supported by an explosive and incendiary component making it a highly capable barrier penetrator and good for usage against light vehicles and armoured infantry. SIG claims the XM1185A1 can penetrate 10mm of RHA at 45° from a range of 600m. 

XM1184A1 - Special Purpose Armor Piercing Ammo with a Depleted Uranium penetrator. Proposed as a "wartime model" equivalent to XM1170 designed purely for penetrating any man portable body armor used by technologically equal countries. Also has a tracer variant.

XM1186 - Special Purpose Depleted Uranium Armor Piercing Fin Stabilised Discarding Sabot round. Proposed for use in emplaced machineguns to defeat VBIEDs at long distances without detonating IED. Also has a tracer variant.


Ammunition Type Damage Bullet Velocity (m/s) Barrier Penetration Armor Piercing
.277 Fury XM1168 (Ball) 15.4 900 3.5 17
.277 Fury XM1169 (Match) 16.2 910 2.8 15
.277 Fury XM1170 (AP) 14.7  984 5.9 120
.277 Fury XM1185A1 (HEIAP) 14 899 8.3 175
.277 Fury XM1184A1 (DU-AP) 11 981 17 290
.277 Fury XM1186 (APFSDS) 10.6 1350 14.5 320
Note: Barrier penetration represents the rounds ability to go through walls and barriers. Armor piercing represents the rounds ability to penetrate body armor plates.