I heard the democrat leadership organized a committee to compete for the Army contract. The design committee, it was said, was given UNprecedented freedom to think. They received only one directive from party bosses that cannot be ignored: The barrel must be U-shaped.
Ehhh,, at one time when the army was interested in killing the enemy the standard was 30-06 and .45acp. I imagine a carbine design with 30-06 as a round could be effective at the specified ranges and strangely enough they have a crap load of it in surplus inventory.