In fact, the M4 was created as the carbine version of the M16, while the M16 is the military version of the AR-15. However, what does that even mean? Well for starters, at a barrel length of 14.5″, the M4 is a carbine-length rifle while the AR-15 has a 16″ standard barrel....
Geissele USASOC URG-I Airborne DDC (military version) BOLT CARRIER GROUP Colt factory assembled bolt carrier group, HP and MPI, phosphated and chrome lined BCG LOWER Colt "M4 Carbine" marked lower receiver, with Colt installed factory lower parts (other than trigger group, trigger...
Seeing how great the 723 was and how the C8 was, the US Army asked Colt to develop their own version in 1984. Testing started immediately with experimentation carbines named “XM4” finding their way into the hands of special forces within a year. Even as much as the military loved this...
It has a phosphate-coated chrome-moly steel barrel, an M4-style barrel extension, and a carbine-length gas system. This model is chambered in 5.56 NATO, with a 1/7-inch twist. On top of that, an F-Marked front sight base and an A2 flash hider are included. You get a forged, ...