Doctrine and why the Grendel has an uphill battle.

[stanc]

As to the merits of the discussion about terminal performance, I'm of the opinion that even the .222 Remington was sufficient, and would have been a better case length to stick with, move the shoulder forward, and use a higher BC projectile with a longer ogive.

The Russians really got it right with the 5.45x39mm cartridge, using a short case that still allows 30rds to be carried in the same magazine profile as a 30rd AR15 mag, which also allows very high BC for caliber projectiles, unlike the 5.56x45. The Russians also used a lower working pressure so that weapon life is more manageable. That little 5.45x39 is a great cartridge as a result. A 5.56-6mmx39 based off that cartridge would have been about ideal for both common infantry and DMR loads, using a BC in the .450 G1 region and higher for the DM load.

I fully agree with all of those points.