The U.S. Army Must Replace the Old M4 Carbine. What Would Make the Ultimate Rifl In choosing a new carbine, the U.S. Army must navigate a maze of requirements Kris Osborn · September 26, 2018 Please leave this field emptyStay Updated with Warrior Maven Subscribe for daily military news and updates delivered straight to your inbox. We don’t spam! Read our privacy policy for more info. Check your inbox or spam folder to confirm your subscription.