I have used the M-4 on deployments to Afghanistan, Iraq and elsewhere. On occasion I have used an AK. Having participated in similar debates for going on six years now, I will offer the following with regard to the reliability of the weapon system:
1. My M-4 has never received more that 10-15 minutes of maintenance daily. On occasion, circumstances prevented me from performing any maintenance. For the record my operational cleaning kit consists of a toothbrush, a rag, a shaving brush and a bottle of lubricant. Despite being subjected to a fair amount of abuse and harsh conditions including sandstorms and helicopter rotor wash, I have never had a malfunction. Ditto the other members of my unit.
2. The condition of some Soldiers weapons borders on criminal. Clearly individuals are not performing even minimal maintenance and their leaders are obviously not checking. In my experience they almost always belong to a combat support or combat service support unit, though I have observed this in combat arms units as well.
3. Many units ignore the condition of their magazines. They fail to clean them and they fail to identify those that need to be replaced. I suspect a large number of the stoppages being reported are magazine related.
4. I have witnessed far more reliability issues with the AK family of weapons that the M-4. I attribute this to the abuse the weapon/magazine/ammunition was subjected to as opposed to a flaw in the design of the weapon.
5. While I do not consider there to be a “problem” with regard to the reliability of the M-4, there is some room for improvement. In my opinion, the HK 416 really puts the issue to bed.
With regard to terminal performance:
1. I have yet to experience a failure using either M855 or Mk262 when I did my part. On one occasion, I was pleasantly surprised by the performance of the Mk262 despite poor shot placement on my part.
2. I attribute the overwhelming majority of reported failures to poor marksmanship/shot placement. I do not think there is a better shooting military in the world but our military’s marksmanship programs leave much to be desired. Consider the Army’s marksmanship program. The average Soldier is given a generous amount of time, to hit a generously-sized, static target with an optically equipped rifle from a stable firing position and needs only hit 58% of their targets to be good to go. The Marine Corps does a much better job of talking up their marksmanship program but in terms of practical performance I have not seen much of a difference. For the vast majority of personnel this is the only training they receive. In the peace-time Army, it was common for misses to be blamed on targets that were too shot up to register a hit. Now we blame them on the ineffectiveness of the round. Question: What does a soldier see when his round fails to neutralize someone? Answer: The same thing he sees when he misses.
3. There have undoubtedly been failures of properly placed 5.56mm rounds to incapacitate personnel. It is also true of the 7.62mm and I am aware of three instances where an individual failed to be immediately incapacitated by a solid hit from a .50 cal. General Krulak, former Commandant of the Marine Corps, once related a story about a member of his platoon in Vietnam who absorbed two hits from a Dshk before managing to silence the gun. It is not unheard of for people to accomplish remarkable feats despite being gravely injured. In our military we usually give them a medal. The fact that there are a higher number of instances being reported for the 5.56mm probably has to do with the fact that it is the most prevalent round on the battlefield.
4. I find it interesting that for all the criticism levied against the M-4 and its purported lack of terminal performance, the M-249 generally escapes criticism despite the fact it fires the M855 from comparable barrel lengths. Go figure...
5. One needs only to take a look at the results of the D.C. sniper to realize that the 5.56mm is more than capable of reliably incapacitating/killing a human being.
A few general observations:
1. The overwhelming majority of the U.S. special operations community uses the M-4, including those who have the latitude to use different weapon systems. Ditto most coalition special operations units including many whose armies issue a different rifle and/or caliber.
2. Having fired a number of assault rifles, I have yet to find one more ergonomically friendly than the M-4.
3. While I have a healthy respect for what a piece of metal traveling at supersonic speeds can do to human flesh, I am generally unimpressed by the terminal performance of the 7.62x39mm. Typically the round passed through the target without disrupting much tissue, which I would note is a common criticism of the M-855.
4. I would never consider a 9mm-anything an acceptable substitute for the M-4 for general use.
I like the M-4 and will make no apologies for it. I have trusted my life to it on too many occasions and it never let me down. Perhaps if my initial exposure to the rifle had been during the Vietnam-era I would be of a different opinion.
Regardless, the M-4 is never going to be all things to all people. No rifle is. That is why Baskin Robbins has 31 flavors. The M-4 remains a popular choice and for good reason. If it does not work for you find something that does.