Back on topic now...
As an aside to this debate I have found further proof of the .270's superiority over the .280 :shock:
Remington is going to offer a 6.8X47 RemSPC ...which is basically a user friendly .270 8)
This excerpt is from an article in Rifle shooter by Gary Paul Johnston....
The 6.8x43mm SPC was conceived by a U.S. Special Operations soldier in a quest to improve the terminal ballistics of the M4 Carbine. The U.S. Army Marksmanship Unit and others assisted the Spec Ops team heading the project. Although the main objective was increased lethality, the new cartridge would go far beyond that in terms of accuracy and performance.
After selecting the .30 Remington as the parent case--a decision that required only slight modification to the M16's bolt face--the case was shortened, given a new shoulder and blown out to maximum capacity for a new high-performance propellant. After testing a variety of bullets in 5.56mm, 6mm, 6.5mm, 7mm and 7.62mm, a bullet of 6.8mm was selected. This .270-caliber, 115-grain projectile has a ballistic coefficient of .350, offering optimum lethality and range.
Remington began to develop the 6.8x43 back in 2002 and is officially introducing it this year as the 6.8mm Rem SPC. As this is written, the cartridge has not been released to the public, but I can tell you that it provides one MOA accuracy out to more than 600 meters. It has a flight path almost identical to that of the .308 Winchester, less chamber pressure than the .223 and fits into the M16 magazine envelope. Tests in 10 percent ballistic gelatin show incapacitation as good or better than the .308.
6.8MMx47 REMINGTON SPC BALLISTICS
BULLET VELOCITY (fps) ENERGY (ft-lbs.)
Muzzle 100 yd. 200 yd. 300 yd. Muzzle 100 yd. 200 yd. 300 yd.
115-gr. FMJ 2,800 2,523 2,202 2,017 2,002 1,622 1,250 1,039
115-gr. BTHP 2,800 2,535 2,285 2,049 2,002 1,644 1,345 1,075
115-gr. MK 2,800 2,535 2,285 2,049 2,002 1,644 1,345 1,075
*24-inch Barrel
As you can see the Special Operations (Marksmanship Unit) of the US armed forces chose the .270 over the .280 :!: 8) :lol: