While the M4-style AR has become America’s gun, there are still plenty of reasons to choose an AR-15 with a 20" barrel. Maybe you want the added velocity that those few extra inches can provide.

The M4/M4A1 5.56mm Carbine is a lightweight, gas operated, air cooled, magazine fed, selective rate, shoulder fired weapon with a collapsible stock. It is now the standard issue firearm for most ...

The gas block functions as an important part of the M4 and M16’s direct impingement system; it funnels gas into the tube and back into the bolt carrier group in order to cycle the weapon. On the ...

Translation: the M4 barrel is so unreliable that special operations forces units need to swap it out with a barrel from a different gun -- and one that actually works in real combat conditions ...

The improved rail will also have to include a low-profile gas block that could spell the end of the M16/M4 design’s traditional gas block and triangular fixed front sight,” the report says.

The M4A1+ solicitation provides a goal for improved accuracy: “The system accuracy for the M4A1+ shall be 5 inches mean radius at 300 meters throughout barrel life (required) and shall be 5 ...

Ultimately, if the move to the M4 is approved by Commandant Gen. Joseph Dunford, the M16 would be used serve exclusively by with support personnel in communities like logistics or admin. Once ...