Okay so rather than start a new thread, I figured I would just continue in this for all of the issues with the Next Gen Squad Weapons Program for
@PrairieFella and others interest.
My main issue with this program is that it upended the entire rational of Requirements, as there has never been a single requirement raised to justify the program, nor any doctrine shift to justify a requirement.
It came out of poorly interpreted Afghanistan data - as well as a perceived need to overmatch opponents in a small arms setting in a LSCO.
The idea a squad needs to overmatch a Platoon Support Weapon (the PKM in 7.62x54R) is a bad take at the best, and a fools errand.
Secondly the were fears created that the Chinese Body Armor wouldn't be defeated by 7.62x51 or 5.56mmx45 NATO ammunition.
No one stopped to look at the testing that showed that M993 and M995 AP ammo would defeat those plates at reasonable engagement distances - and some other folks also cooked the books on what the armor level was on Chinese Plates as well.
Years ago when at KAC, I had built some .260 Remington, 6.5 Creed, and 7-08 SR-25 uppers for a test. At the time .260 Rem was chosen as a stop gap system - mainly as at the time the ammo was more developed for mid range (500-1000m) shooting.
Joint Small Arms Program had been conducting studies for a while on what the optimal cartridge was, in an attempt to get a shootable longer range system that also had terminal performance improvements - and 6.5 won JSAP had been testing the CaseTelescoping Ammo (CTA) systems in 5.56mm then 7.62mm to see apples to apples across from the conventional cartridge systems.
General Miller when the FORSCOM Commander had issued a requirement for a 7.62mm Select Fire Carbine as an Interim Battle Rifle - it was fortunately cancelled when he shot the JSAP 7.62 CTA Machine Gun - but it shoved him into the belief that one needed a new cartridge and weapons systems.
SOCOM had adopted the 6.5 Creedmore cartridge as a higher efficiency medium round to use in place of 7.62x51mm NATO. As it is a parent 7.62x51 casing, it fit in magazines and M37 link - and (theoretically) just required a barrel change to use in most systems.
The US Army then decided that the projectile they wanted "couldn't be done" in a 6.5 Creedmore and settled on a 6.8mm projectile -- and provided minimum ammunition requirements and the Next Generation Squad Weapons was born.
Currently named NGSW-R (Rifle) XM-7, and NGSW-AR (Automatic Rifle) XM-250
Sig ended winning the downselect with a 6.8x51 cartridge and their two offerings.
No one seems to do any reality testing with the pressure that was being demanded in the systems to get the projectile to the desire velocity - so one ended up with 85-110k PSI chamber pressures.
Anyway after a slew of defects the Army started delivering the weapons to the National Guard (hiding them away one might think).
I could go on a lot more - but it was a stupid program that didn't understand the reality of the battlefield.