.277 Wolverine

.277 Wolverine
TypeRifle
Place of originUnited States
Production history
DesignerMark Kexel, Mad Dog Weapon Systems, Inc.
Designed2014
Specifications
Parent case5.56×45mm NATO
Case typeRimless, Bottleneck
Bullet diameter0.277 in (7.04 mm)
Neck diameter0.3089 in (7.85 mm)
Shoulder diameter0.356 in (9.04 mm)
Base diameter0.377 in (9.58 mm)
Rim diameter0.378 in (9.60 mm)
Case length1.530-1.535 in (38.86 mm, trim) to 1.545 in (39.24 mm, max.)
Overall length2.26 in (57.40 mm) max. COAL (typical)
Rifling twist1:7 (subsonic/supersonic), 1:11 (supersonic)
Primer typeSmall rifle
Ballistic performance
Bullet mass/type Velocity Energy
85 gr (6 g) 2,800 ft/s (850 m/s) 1,480 ft⋅lbf (2,010 J)
90 gr (6 g) 2,750 ft/s (840 m/s) 1,510 ft⋅lbf (2,050 J)
95 gr (6 g) 2,650 ft/s (810 m/s) 1,480 ft⋅lbf (2,010 J)
100 gr (6 g) 2,600 ft/s (790 m/s) 1,500 ft⋅lbf (2,000 J)
110 gr (7 g) 2,500 ft/s (760 m/s) 1,525 ft⋅lbf (2,068 J)
Test barrel length: 16 in
Source(s): [1]

The .277 Wolverine (6.8x39mm) is a wildcat cartridge. It is a multi-purpose mid-power cartridge with increased ballistic performance over the AR-15's traditional .223 Remington (5.56×45mm NATO) cartridge. The use of a modified 5.56 case means that at minimum, only a new barrel is needed to convert any 5.56-based firearm to .277 Wolverine.[2]

  1. ^ "277 Wolverine - Mad Dog Weapon Systems". Maddogweapons.com. Archived from the original on 1 October 2020. Retrieved 2015-06-17.
  2. ^ Hull, John. "The .277 Wolverine: Birth of a Wildcat". WesternPowders.com. Western Powders, Inc. Archived from the original on 2015-03-12. Retrieved 2015-12-31.