How could or should the 6.5 mm Grendel be improved?

[Trooper]

It may or may not, depending upon:

a. Is it better to have a caliber that is excellent for, say, 90% of combat theatres, but inadequate for 10%, or a caliber that is excellent for 10%, and usable for the other 90%?

b. Is it better to have the simplified logistics of a single, universal caliber versus two or three specialized calibers?

c. Is the weight penalty of a universal caliber for Key Leaders, RTOs, FOs, etc, unacceptable or tolerable? (Use of the M14/M60, FAL/MAG, and G3/MG3 before adoption of 5.56x45 would seem to indicate that the weight of universal caliber weapons is tolerable.)

If you consider that the pistol is seen as a PDW then a more robust PDW like the FN P90 (5.7x28) or the HK MP7 (4.6x33) might be of interest. Inside the wire (on a FOB or in garrison here in the states) a PDW makes sense. I do not want to have be dragging a larger rifle around. But outside the wire in a combat arena, I want general purpose rifle (GPR). The problem is that as a GPR, the M4 (5.56x45) is too light and the M14/M110 (7.62x51) is too heavy. A GPR using a 6.5mm round makes more sense.

What you have suggested, which has been a topic of discussion within NATO, is whether we need a PDW that is more effective than are our current 9mm pistols (M9/M11). While the M4 does a personal defense mission, for many of our troops a smaller PDW might be wise.