By Blaise Uriarte

The Basics
The M4 is the standard carbine for the US military. It is a derivative of the M16 rifle. The M16 is a selective fire, gas operated, direct impingement weapon. Feeding and extraction is done by means of a rotating bolt. The upper and lower receivers are machined from aircraft grade anodized aluminum, with the barrel and firing components made from steel.
The M16 series of rifle was designed in 1956 by Eugene Stoner for the Armalite Corporation. The patent was purchased by Colt in 1959, and the M16 first saw service for the US Air force in 1962.
The weapon was fielded in Viet-Nam, but to mixed success. It was originally issued without a chrome lined barrel, and with substandard ammunition. Also owing to the mixed success of the original M16 rifles, was the fact that they were issued without field cleaning kits, as cleaning was deemed unnecessary by the war department.
The rifle has evolved significantly since Viet-Nam. This Daniel Defense M4 features the standard Mil-Spec six position buffer tube, with the Mag-pul MOE collapsible stock, mid-length gas system with a quad rail for end, and a vertical fore grip. This rifle is also fitted with an EoTech 512 holographic sight.

The Ammo
This rifle is chambered in the 5.56x45mm NATO cartridge. It can fire the lower powered .223 Remington interchangeably. The cartridge generates about 2900 feet per second in a 16.5 inch barrel, and about 1200 foot pounds of energy with a 63 grain bullet.
Terminal ballistics are adequate, as the round is designed to fragment on impact. This effect is diminished at longer distances however. Maximum effective range for this round out of a carbine barrel is about 600 yards.
The Range Test

Test ammo was American Eagle Brand 5.56 and .223 Remington. I found recoil to be negligible on this platform, thus it is very easy to hold on target during rapid fire. The rifle is very ergonomic and comfortable as well. There were no malfunctions during this range trip either.
The rifle grouped within an 8 inch circle at 25 yards, shooting off hand. I found the EoTech sight to be distracting. The reticle covered the entire target at that distance. While this makes for fast target acquisition, it may be a hindrance for long range shooting.

I am sure that greater accuracy can be achieved by shooting from a bench rest or prone position; however I was unable to shoot this rifle in that manner at this facility. More than likely, one would find themselves kneeling or moving in a combat scenario, so it is important to practice those shooting styles.
The Pluses
This weapon proved to be accurate, reliable, and very comfortable to shoot. Furthermore it is light weight and versatile. With the collapsible stock, weight and controllability of this rifle it is easy to see why the military relies on this gun. I would not hesitate to recommend this as a weapon against the undead. I would very much like to see how it would do at longer ranges, but I have little doubt that it would perform well. All and all this is a good rendition of the Stoner design.
The Minuses
The direct gas impingement system is high maintenance. You must keep it clean or it will be much more prone to develop problems than a piston driven gun. There is a lot of carbon buildup in the receiver and bolt carrier group are that needs to be cleaned periodically. As long as the weapon is maintained, it will stay reliable.
Conclusion
I would rate this gun very well. It is extremely easy to control, maneuverable, light and handy. The Daniel defense is very well made, and would make a great weapon against the undead. Of course it is just a paperweight if the user is untrained. Remember, stay vigilant and be prepared.
Special Thanks
Special thanks are extended to my good friend Josh for letting me use his rifle.