New Cartridge Developments and Implications for Dismounted Infantry Soldiers

[Tony Williams]

I think that both the 6.8mm SPC and 6.5mm Grendel were very good attempts to squeeze the maximum out of the constraints of the AR-15 package; they just have slightly different pros and cons.

The problem as I see it is the AR-15: the action is too short to accommodate the optimum compromise military round.