6.8 mm Remington SPC

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6.8x43mm Remington SPC

6.8 mm Remington SPC (Left) as compared to the 5.56x45mm NATO cartridge (Right)
Type Rifle
Place of origin Flag of the United States United States
Production history
Designer Remington, SOCOM
Designed 2002-2004
Specifications
Parent case .30 Remington
Case type Rimless, bottlenecked
Bullet diameter 0.277 in (7.0 mm)
Neck diameter 0.298 in (7.6 mm)
Shoulder diameter 0.402 in (10.2 mm)
Base diameter 0.421 in (10.7 mm)
Rim diameter 0.422 in (10.7 mm)
Rim thickness 0.049 in (1.2 mm)
Case length 1.676 in (42.6 mm)
Overall length 2.315 in (58.8 mm)
Ballistic performance
Bullet weight/type Velocity Energy
115 gr (7.5 g) (7.45g) 2,625 ft/s (800 m/s) 1,759 ft·lbf (2,385 J)
Test barrel length: 24 in (609.6 mm)
Source: Remington [1]

The 6.8 mm Remington SPC (or 6.8x43mm) is a new rifle cartridge that was developed with collaboration from individual members of US SOCOM.[2] Based upon the .30 Remington cartridge [3], it is midway between the 5.56x45mm NATO and 7.62x39mm in bore diameter and velocity with more energy than both. It is particularly adaptable to current 5.56 mm NATO firearms, the cartridge overall length being comparable.

Though ballistically similar to the 1950s-era .280 British, improved propellant powders allow the 6.8 mm a smaller case. The 6.8 mm SPC (Special Purpose Cartridge) has a muzzle velocity in the 2,400 feet per second (730 m/s) range from a 16 inch (406 mm) barrel using a 115-grain bullet.

Contents

[edit] Performance

The 6.8 mm Remington SPC is designed to deliver 44% greater energy than the 5.56 mm NATO at 100-200 meters.[4] When compared to the more powerful and well-established 7.62x51mm NATO cartridge, the 6.8 mm falls short in all of these areas, but has less recoil and is more controllable. While the 6.8 mm generates around 1,759 ft·lbf (2385 J) of muzzle energy with its 115 grain bullet (note: this figure is from an unrealistic 24" bolt-action test barrel), the 7.62 mm NATO (M80) fires a 147 grain bullet at 2,750 ft/s for 2460 ft·lbf of energy (838.2 m/s for 3335 J).

While the round is generally intended for use at shorter ranges, this handicap somewhat dampened the initial enthusiasm over the SPC round, and given competitors like the 6.5 Grendel or improved 5.56 mm rounds an opportunity to compete for acceptance. Many criticisms fall short considering the majority of military engagements (even with modern optics) occur inside 300 m (U.S. Army Continental Army Command Operations Research Office ALCLAD study, and Gen. S.L.A Marshall, cited on p. 15, "The Complete AR-15/M-16 Sourcebook", Duncan Long, Paladin Press 1992, 2007)

The first major manufacturer to offer a 6.8 mm Remington SPC chambered version of the AR-15 was Barrett Firearms Company, offering the Barrett M468. By 2007, most major manufacturers of AR-15 type rifles for the civilian gun market, such as Bushmaster Firearms International, DPMS Panther Arms and Rock River Arms were also producing 6.8 mm Rem SPC carbines. Ruger Firearms produces a 6.8 mm version of their popular Ruger Mini-14 series carbine [5].

[edit] Muzzle velocity from a 24-inch (610 mm) barrel

  • 7.45 g (115 gr) Full Metal Jacket (FMJ): 2,625 ft/s (800.1 m/s)
  • 7.45 g (115 gr) Boat Tail Hollow Point (BTHP): 2,624 ft/s (799.8 m/s)
  • 7.45 g (115 gr) Sierra Match King (SMK): 2,625 ft/s (800.1 m/s)

[edit] See also

[edit] Notes

  1. ^ Remington Web Page: 6.8 SPC Velocity/Ballistics
  2. ^ Not a private endeavor or fully sanctioned government project
  3. ^ 30 Rem
  4. ^ 6.8 SPC Velocity/Ballistics - hot loadings
  5. ^ Information on the 6.8 SPC Mini

[edit] External links