The United States’ small arms acquisition process has almost always been in the shitter, and has gotten worse since dis-establishing the national armories – not that it was any good when they were tripping all over themselves with M14 - M16 politics.
The Infantry Center does a horrible job articulating the foot Soldier’s basic rifle and small arms requirements.
The US Army’s Labs provide welfare for engineers and Ph.Ds.
The United States Special Operations Command has leverage over Mother Army because it has its own R&D and acquisition money authorized under the Nunn-Cohen Act of 1987 which gave birth to SOCOM.
If the Army adopts a SOCOM-peculiar item it must (by law) buy the items for ALL US Army Special Operations Command Soldiers and units. If Mother Army does not standardize the item SOCOM buys the equipment for SOCOM Operators. This explains why, when you see a General Purpose Forces Soldier standing next to an SF Soldier there are differences in kit.
The SF Soldier may have the latest cutting edge equipment, and it should fit (off-the-cuff examples being BALCS armor or a separate plate carrier; the Universal Night Sight; perhaps a 45 caliber pistol; free-floating rail on his M4 or Shorty Mark 18; a 300 or 338 Lapua sniper rifle; different special environment clothing, etc.).
As industry releases something good, USSOCOM, USASOC, and Special Mission Units have the option of getting the Combat Development guys to the designers in a hurry. When Bill Geiselle showed me his first triggers at Camp Perry we were able to get them for AR-10T prototypes and that’s when I first asked him when he’d have a select-fire version ready.
The Army’s system sucks. The Navy system seems easier to work with, though historically gullible and in love with their own work (often falling into what appear to be really chummy and inappropriate relationships with certain vendors).
Just my two unofficial cents as an end-user. I am NOT a manufacturer, an Acquisition official, a contract, ordering, or supply officer.
In the past I HAVE been a trigger-puller, a commander, a requirements and doctrine writer-recommender, a trainer, a tester, and an approving officer.
