Grendel as a Universal Infantry Cartridge

[SHORT-N-SASSY]

Look to have a general purpose (universal) cartridge it is going to have to be between 6.5 and 7mm. The 6.5mm works better due to less recoil.

The next aspect is getting the round to 2500 fps out of the barrel using a 140 grain bullet. That is the standard, set by the 6.5x55 Swedish Mauser. So far the .260 Rem, the 6.5 Creedmoor and and the 6.5x47 Laupa meet those requirements but with longer cases. As do wildcats like the 6.5 BRM which is based on the .30-30 case. The problem is that we can get a 140 gn. bullet to go 2500 but it takes a longer case than would fit into the current AR platform.

So could we make 6.5mm GPC that pushes a 140 gn. bullet 2500 fps? And make it smaller than a .308 (7.62x51)?

It's been reported that 2650 - 2700 fps, with the 139-grain Lapua Scenar projectile, has been achieved, from a 22" bolt-action rifle chambered for the 6.5 Grendel. Was that 139-grain Scenar loaded to AR-15 magazine length, or extended? If extended, to what overall length?

It's been reported that "Big Bolts" can operate at/up to 60,000 psi, in the standard-length AR-15 action. Unencumbered by the limitations the laws of Bolt Thrust impose on the 6.5 Grendel, in the standard AR-15 Bolt-Barrel Extension, what velocities can be achieved in a "Big Bolt" AR-15?

ETA: LRRPF52 Reply was posted, while I was typing mine. I think it's fair to state that his suggestion represents the solution.