The US Army’s plan to wrap new technologies and commercial off the shelf (COTS) improvements into the M4A1 rifle has apparently been canned. The program, called M4A1+, was originally intended to upgrade the M4A1 fleet with new COTS rails, back up sights, flash hiders, triggers, and other improvements, but it seems the service will push forward with the basic 22-year-old M4A1 design for now. ArmyTimes reports:

“The Army issues market surveys all the time to assess if there’s any new technologies that it might want to look at. In this instance, there weren’t,” Picatinny Arsenal spokesman Pete Rowland in an email. “Case-closed for now.” The M4A1+ market survey requested solutions that included an extended Picatinny rail (to both allow a shooting technique with a straightened forward elbow and more accessory-attachment options), as well as a floating barrel to enhance accuracy. Other improvements sought were: a flash suppressor; a brownish color for new parts to help camouflage; removable iron sights; and an optional sniper-style single-stage trigger specifically for squad marksmen. The upgrades were to “seamlessly integrate with the current M4A1 Carbine … without negatively impacting or affecting the performance or operation.” At the time Lt. Col. Terry Russell, project manager for individual weapons at Picatinny Arsenal, said the Army was “very confident that these already do exist, or that (companies) can develop them for us in short order.” But the offerings apparently did not add enough value for the Army to pull the trigger.

The M4A1 offers substantial improvement over the basic M4, including fully automatic selector setting, ambidextrous selector levers, and a much heavier barrel contour originally created to support extended fully automatic fire from SOCOM reconnaissance teams. While the M4A1+ improvements could have augmented the rifle’s configuration slightly, taken altogether they represent only a very modest possible improvement over the existing M4A1. The biggest possible improvements would have been the change to a low profile gas block, and a longer, lighter rail (possibly even utilizing a negative footprint mounting system like Keymod) than the somewhat small, heavy, and antiquated KAC RAS 1913 rail. It seems likely to me that in the future the Army will pursue these developments regardless of the M4A1+ program’s cancellation, that is provided that the service moves quickly enough that such improvements can arrive before the replacement of the M4 with something new.