The M4-series Carbine achieves over 80% commonality ... Compared to the M4 , the M4A1 has full auto capability, a consistent trigger pull, and a slightly heavier barrel. The heavier barrel is ...

The M4A1 rifle, which uses 5.56x45 mm NATO ammunition, is often compared to its civilian version, known as the AR-15. It is characterized mainly by a 37 cm barrel, although 41 cm barrels are also ...

The M4A1 rifle, which uses 5.56x45 mm NATO ammunition, is often compared to its civilian version known as the AR-15. It is characterised mainly by a 14.5-inch barrel, although 16-inch barrels are ...