About 277 Fury
277 Fury or 6.8×51mm, is a centerfire, rimless bottlenecked rifle cartridge developed by SIG Sauer for the United State’s Army’s Next Generation Squad Weapon Program (NGWS).
In December 2019, the 277 Fury cartridge was announced for non-military usage with the goal of creating a more capable and versatile cartridge that could offer better performance in terms of range, accuracy, and terminal ballistics compared to 5.56 NATO.
The .277 Fury cartridge uses a case that is the same length and diameter as the .308 Winchester.
Each "hybrid" 277 Fury cartridge case has a stainless-steel base coupled to a brass body via an aluminum locking washer.
Stainless steel has a significantly higher yield strength than brass, allowing engineers to use higher maximum average pressure (MAP) chamber pressure levels.
On April 19, 2022, the United States Army announced that it had selected SIG Sauer to build the XM5 rifle to (partly) replace the M4 carbine, while the XM250 automatic rifle was to replace the M249 SAW in the LMG role.
Operational testing of the XM5 rifle, XM250 automatic rifle, XM157 fire control optic platform agnostic unit, and the 6.8×51mm ammunition squad weaponry is expected to begin in 2024.
However, this does not guarantee actual widespread future issues. The military designation for this round is 6.8 common cartridge.
.277 Fury Ammo Dimensions
Caliber
The .277 Fury cartridge typically has a caliber of approximately 6.8mm, which is larger than the standard 5.56x45mm NATO cartridge used by the U.S. military.
Case Length
The case length of .277 Fury ammunition is approximately 41mm (1.61 inches).
Overall Length
The overall length of a loaded .277 Fury cartridge can vary depending on the specific bullet type and weight but generally falls within the range of 2.2 to 2.3 inches.
Bullet Diameter
The bullet diameter for .277 Fury ammunition is around 6.8mm, which is consistent with its caliber.
.277 Fury Ballistics Performance
BULLET MASS AND TYPE / VELOCITY / ENERGY
135 gr (9 g) Hybrid Match
3,000 ft/s
2,694 ft
135 gr (9 g) Elite Ball FMJ
2,750 ft/s
2,267 ft
140 gr (9 g) Hunting
2,950 ft/s
2,706 ft
Popular 227 Sig Furry Types
277 SIG Fury, 130GR Elite Ball FMJ
Muzzle Velocity
- 16in @ 2750
- 24in @ 3000
Muzzle Energy
- 6in @ 2267
- 24in@ 2697
Ballistic Coefficient (G1)
- 0.475
277 SIG Fury, 130GR Venari Soft Point Hunting
Muzzle Velocity
- 2710 fps
Muzzle Energy
- 2120 ft-lb
Ballistic Coefficient (G1)
- 0.409
277 SIG Fury Hybrid, 150GR Elite Bonded Polymer Tipped
Muzzle Velocity
- 16in @ 2830
- 24in @ 3120
Muzzle Energy
- 16in @ 2667
- 24in @ 3242
Ballistic Coefficient (G1)
- 0.500
277 Furry vs .223 Ammunition
Caliber and Bullet Size
.277 Fury: The .277 Fury cartridge has a larger caliber, approximately 6.8mm. This means it accommodates bullets with a larger diameter, typically around 6.8mm.
223: The .223 Remington cartridge, commonly known as .223 ammo, has a caliber of approximately 5.56mm and is designed for bullets around 5.56mm in diameter.
Ballistic Performance
.277 Fury: The larger caliber of the .277 Fury allows for heavier bullets with better long-range performance and energy retention. It offers greater stopping power and is suitable for medium to large game hunting.
.223: .223 ammunition is known for its flat trajectory and relatively low recoil. It is primarily used for varmint hunting, target shooting, and military applications, with effective ranges typically up to 300-400 yards.
Uses
.277 Fury: The .277 Fury is designed for enhanced performance in military and law enforcement applications. It's intended to replace the 5.56x45mm NATO cartridge and provide improved terminal ballistics and range.
.223: .223 ammo is commonly used in civilian rifles for target shooting and varmint hunting. It is also the standard cartridge for the M16 and M4 rifles used by the U.S. military.
Terminal Ballistics
.277 Fury: The .277 Fury is designed to offer better terminal ballistics and stopping power compared to the .223. It can provide more consistent and effective results, especially at longer ranges.
.223: While .223 ammunition can be effective within its intended range, it may not offer the same level of terminal performance as the .277 Fury, especially when dealing with larger game or heavily armored targets.
Recoil
277 Fury: Due to its larger caliber and increased power, the .277 Fury generally produces more recoil than .223 ammunition. Shooters should be prepared for greater felt recoil when using .277 Fury.
.223: .223 ammunition is known for its manageable recoil, making it suitable for shooters of various experience levels.
Availability
.277 Fury: As of my last knowledge update in September 2021, .277 Fury ammunition may have been less widely available than .223 ammunition due to its relatively recent introduction.
In summary, the .277 Fury and .223 ammunition are distinct cartridges designed for different purposes.
The .277 Fury offers enhanced long-range performance, stopping power, and terminal ballistics, making it suitable for military and law enforcement applications.
On the other hand, .223 ammunition is well-suited for civilian use, varmint hunting, and target shooting, with a reputation for manageable recoil and accuracy within its effective range.