From our friends at the Woodpile Report is this experimental model to increase velocity and lower weight.
"Among their goals is hypervelocity for extended range lethality from standard sized weapons, and full-sized rifle velocities with firearms that are half the weight, half the length, and hold more ammunition than the Army’s M4 carbine."
"Among their goals is hypervelocity for extended range lethality from standard sized weapons, and full-sized rifle velocities with firearms that are half the weight, half the length, and hold more ammunition than the Army’s M4 carbine."

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