It'd be a great choice for shooting the 600-yard National Match Service Rifle course at 600 yards. On a range, on a sunny day, with windage flags flying and an ambulance handy nearby. But a rifle that weighs 11 pounds before adding a telescopic sight and mount, , much less night vision equipment and a suppressor, and has to be carried in a plastic suitcase to protect the optics? I went through combat arms basic training with the M14, carried M14s, M14E2s and M21 rifles on combat ops and got my first combat kill through an ANPVS1 starlight scope when I was nineteen; I am near 70 now. and you want to put a SOPMOD stock on it, eliminating the in-buttstock cleaning kit, and adding another piece of rattle-bait to the poor shooter's load, for a guy- or girl- who has to keep up with an infantry squad made up of folks armed with the M4 because the M16A2 was too long and heavy?
I do not have the answer. For myself, it'd probably be a 7,62 bullpup. For the Russians, and their bloddy decade in Afghanistan, the answer was the SVD Dragonov. Of what we have now, the M14-based M25, designed by and for Special Forces, NOT average first-enlistment grunts, isn't too bad. But I suspect that an entirely new weapons platform is forthcoming. And then some bright character will suggest giving everybody one....
When the Soviets finally pulled out of Afghanistan, they were issuing 3 or 4 SVD sniper rifles per squad. The maximum range of an RPG-7 antitank rocket launcher is 900 meters; a good SVD will reach out and touch a little farther than that, given good ammo.
And we may be fighting in cities and towns soon, MOUT in Army-speak. Up and down stairs, with ranges measured in both living room distances and city blocks away, with a three-and-a half foot long, 14-pound-plus rifle and ammo? Don't think so.
I’d say go back to the M-40 and add a few modern touches. It worked well enough for me.
L
Some folks recommend an AR-10 variant. I’ve shot a few an they seem to all have one thing in common, they’re friggin heavy. As you say, it may require a completely new design.
I know, it's another caliber, and the US Army don't do knew calibers, ever since they insisted on making the M-1 Garand a 30-06 to use up warehouses full of that caliber. (The Garand was designed to shoot a 6.5 and hold ten rounds, I believe.)
"NOT A 6.5 Creedmore above, and that is a 1X4 Elcan."