12-07-2011, 05:17 AM
With the 6.8, you would want to neck it down to 6.5mm, but a 6.5 SPC or 6.8 SPC with longer projectiles for an LMG would make a COAL close to 7.62 NATO. What I like about the Grendel case is that I can still have a relatively short COAL compared to 7.62, and that means more optimum space utilization on the soldier's load. An ammo bag closer to what is used on the SAW would be wonderful, whereas the ammo cans used on the PKM are way too bulky, as would be a 7.62 ammo bag that attaches to the weapon...especially for the curve ball I have for ammo placement on one of the LMG designs I have.
The .277 projectiles require way more velocity to get them to do what a moderate velocity 6.5 will do...I learned that with the 140gr 6.5 Berger VLD for my .260 Rem versus the .277 140gr Berger VLD for my .270 Winchester: The .270 requires 250fps more muzzle velocity to match the .260 Rem at 1000yds, and the .260 still has it beat for wind deflection.
These factors are what make the Grendel case more appealing to me for an LMG. The one possible advantage I see with the 6.8 case is the shoulder angle might be more conducive to feeding, but the inverted feed ramp of a belt fed would be tapered to articulate with whatever cartridge it was chambered in.
The .277 projectiles require way more velocity to get them to do what a moderate velocity 6.5 will do...I learned that with the 140gr 6.5 Berger VLD for my .260 Rem versus the .277 140gr Berger VLD for my .270 Winchester: The .270 requires 250fps more muzzle velocity to match the .260 Rem at 1000yds, and the .260 still has it beat for wind deflection.
These factors are what make the Grendel case more appealing to me for an LMG. The one possible advantage I see with the 6.8 case is the shoulder angle might be more conducive to feeding, but the inverted feed ramp of a belt fed would be tapered to articulate with whatever cartridge it was chambered in.