New Army "Caliber Configuration Study"

[stanc]

7grams is 108grains and 8g is 123gr. The 6.5 Grendel ALREADY matches the "range" — the external ballistics — of the PKM.

When using HPBT match bullets, 6.5G may match trajectory and drift of 7.62x54R FMJ ball. The question is, how would a 6.5G 108gr Ball load compare?

I very much doubt that you'll be able to get anywhere close to matching the BC of Scenars and MatchKings in a service grade ball projectile.

The question is whether the terminal performance of its 123gr bullet is acceptable relative to the PKM's 147gr bullet.

Why do you keep talking about a 123gr bullet, John? That weight appears to be feasible only with a lead-core bullet, and the military is moving to lead-free projectiles for general-issue, ball ammo.