contract says they won't be "bringing a gun back" they want a off the shelf ready model.
so
XCR-m fits the bill.. but the manufacture is probably to small to supply the army "now". Also insert top brass hate on for the company owner, not a chance of them getting it.
FN FAL? pft... not a chance, the only commercial ones on the market right now are small runs and of poor quality mostly made overseas.
M14... no they want a modern gun, one that doesn't require a lot of gunsmithing and gentle hands to keep accurate.
FNAR, its a contender,
AR-10.... this is my bet. it will be one of the newer models, the US army will be able to use m 16 triger parts, and some of the gunsmithing tools. less retraining as it's maintenance and operation is almost identical to current weapons systems used.
I could see them taking the smith and wesson M&P10; its is a very excellent rifle ,meets the specs, its very accurate, very reliable with all ammo, reputable manufacturer "made in america" with capacity to produce.