03-14-2012, 02:40 AM
Yes, 5.56 M193 and M855 rely on thin jackets and high velocity to cause massive tissue destruction. It comes down to the fact that there is more of a likelihood to have different loads of the same caliber for different duty positions, and belt fed weapons should not have the same loadings as a carbine. In a belt-fed, we want longer-range terminal performance, to include barrier penetration and light skinned vehicle defeat capability.
In a carbine for every rifleman, key leader, RTO, assistant gunner, ammo bearer, and grenadier, we don't want extreme barrier penetration and long-range terminal performance when it means increased recoil, decreased mag capacity, increased soldier's load, and over-penetration in the distances that the unit relies on riflemen to reduce targets (within 50m usually).
Since 5.56 does such an amazing job out of such a small package, it will be hard to replace. I am in strong favor of a High Performance Intermediate Cartridge like the Grendel for a new Multi-Role belt-fed LMG, which could replace the 7.62 GPMG in the dismounted role. That will take at least a 130gr bullet at anywhere from 2600-2750fps, although 2600fps is plenty. A mass-produced 130gr FMJBT with lead core would have no trouble facilitating a .500" G1 BC.
With a two-caliber system of 5.56 and 6.5 Grendel, you would cut soldier's weight, increase maneuverability, and realize some increases in barrier penetration with higher sectional density bullets.
In a carbine for every rifleman, key leader, RTO, assistant gunner, ammo bearer, and grenadier, we don't want extreme barrier penetration and long-range terminal performance when it means increased recoil, decreased mag capacity, increased soldier's load, and over-penetration in the distances that the unit relies on riflemen to reduce targets (within 50m usually).
Since 5.56 does such an amazing job out of such a small package, it will be hard to replace. I am in strong favor of a High Performance Intermediate Cartridge like the Grendel for a new Multi-Role belt-fed LMG, which could replace the 7.62 GPMG in the dismounted role. That will take at least a 130gr bullet at anywhere from 2600-2750fps, although 2600fps is plenty. A mass-produced 130gr FMJBT with lead core would have no trouble facilitating a .500" G1 BC.
With a two-caliber system of 5.56 and 6.5 Grendel, you would cut soldier's weight, increase maneuverability, and realize some increases in barrier penetration with higher sectional density bullets.