01-02-2019, 02:41 AM
LRRPF52 Wrote:The Six8 PMAGs have more thickness on the front and rear walls of the mag, so I can see why LWRC would want to add magazine well length to accommodate the additional thickness of the PMAG.
The Army Ordnance guys had one dude who wanted to improve on the .222 Rem SCHV concept back when several cartridges were still being hammered out.
Initial problems with the .224" 68gr projectiles retaining energy for steel helmet perforation had 2 different suggestions for dealing with that requirement:
* Stoner's approach - add a boat tail to the bullet to help it retain energy, and run higher pressure with more case capacity to create faster mv and better impact velocity. They blew the shoulder forward and launched a 55gr bullet as fast as they could with the new experimental .222 Remington Special case.
* Minority individual engineer suggestion - Take the 25 Remington case, neck it down to .224, re-design the receivers, bolt, and mags for a new cartridge with more case capacity, slightly fatter, longer bullets with higher BC.
Stoner and ArmaLite saw this as an attempt to slow-roll the AR15 so that it would die in constant engineering changes from the Army, effectively killing the AR15 in its infancy. It's only so often that stars align with the right people in the right places to allow innovation to move forward and root itself to gain widespread market success.
6.5 Grendel fights against that reality with its performance and the welcome home of the widespread AR15 receiver set and parts availability.
Any attempts to move forward with something new will require another alignment of stars.
Ok so going off the fact we know the 68 lower is longer. In my aero lower with a windowed cpd mag I can load and run loads at 2.355 and they feed perfectly.
So most likely a windowed 68 polymer mag would put loads close too if not just past 2.400.
Think I might order up a 20 round 68 pmag too do a lil hands on testing.