Yes, but SWAT uses M4A1 with mounted pistol grips. As do FBI tactical.
Dean quickly did the math. Two zombies in the hall way and at least five in the office. The extended clip holds 30 5.56X45 MM Nato armor piercing round, plus one in the chamber. Assuming he takes down the seven zombies with one shot he is set, but any more could bring up complications later. Thoughts kept flowing through his head. He almost froze. Almost.
Then something in his head clicked and his brain fell silent. He stared threw the ACOG scope [because i took a SWAT tactical rifle it has extended clips, acog scope, and pistol grip. thats why i specified it was the M4A1]. He flipped the safety off and fired two shots on Semi-auto, each bullet tearing through the zombies heads with a brilliant spray of coagulated blood. He moved foreward, turned towards the offices and started to pick the zombies off being conservative with the ammo. When all was said and done, Dean only wasted ten shots, leaving 21 left in his first clip.
The M4A1 SOPMOD (basically the gun i am using) is used in SWAT and FBI tactical, so it is logical. :^P plus it isn't like we have infinite ammo. Althou some one should have grabbed extra ammo incase we run dry.