Re: Is a 260 remington the same as a 6.8mm?
Nope , the 260 is based on the 308 and 243 winchester cases where the 6.8 SPC is based on the 30 remington case I believe , shorter case less volume. Also the 6.8 SPC has a bore diameter of .277" same as 270 Winchester and the 260 Rem hase a bore diameter of .264" same as the 6.5-284 and 264 Win mag.
The 6.8 SPC was desgined to be fitted in the standard AR platform with little modification to the gun but adding an increase in power on target. I think that this is a big waste of time and effort on the military's part , the 5.56 NATO is a good round if the proper bullets are used and if the bore diameter "has" to be increased simply necking the 223 up to a 6mm and shooting 80gr bullets would make for a balisticaly better round and a hell of alot less work to the stardard issue weapon.
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