No, Virginia, “M4A1+” Upgrades Don’t Prove The M4 Is Flawed

    The 2007 Dust Tests have come and gone. The IC Competition has completed. The M4 has remained the standard infantry rifle, and been upgraded to the heavy-barreled M4A1 standard. More upgrades are on the horizon, as part of the US Army’s effort to improve current infantry small arms. These “M4A1+” upgrades should indicate a certain level of satisfaction with the weapon – if the Army were unsatisfied, after all, surely they would divest themselves of the rifle entirely, rather than trying to improve it further.

    That is not, however, how the news media, egged on by one Maj. General Robert Scales, Jr. (Ret), perceives it. The Washington Times has released an article slamming the M4A1+ upgrades as being a tacit admission that the M4 is flawed and should be replaced, citing Scales as an expert:

    The Army is asking the gun industry to build new components for its soldiers’ primary weapon — the M4 carbine — a move that experts say is a tacit admission that the service has been supplying a flawed rifle that lacks the precision of commercially available guns.

    At a recent Capitol Hill hearing, an Army general acknowledged that the M4’s magazine has been responsible for the gun jamming during firefights.

    On the federal government’s website, the Army announced a “market survey” for gunmakers to produce a set of enhancements to essentially create a new model — the “M4A1+.” It would include a modular trigger, a new type of rail fitted around a “free floating” barrel and other parts. The upgrade is supposed to improve the rifle’s accuracy and reliability.

    Gen. Scales said the Army’s new solicitation is further proof of the carbine’s shortfalls.

    “It’s another attempt by the Army to make the M4 look good,” he said. “If the Army wants to improve the M4, fine. But it’s not a weapon suitable for high-intensity, close combat in extremes against an enemy who is basically matching us in weapons performance in a close fight. Everybody knows the weapon has flaws.”

    Mr. Scales said the M4’s basic shortfall is that it uses gas, or direct, impingement to extract and expel its shells as opposed to a piston system. A piston firing mechanism is in the prolific AK-47, which runs cleaner and cooler but is considered slightly less accurate.

    One consistent complaint about the M4, even from users who love the gun, is that it requires frequent cleaning. Another frequent gripe is that the 30-round magazine is prone to jamming.

    “It’s what everyone has known for 50 years,” Mr. Scales said. “There is no mystery here. Every report, every study, every anecdotal piece of evidence has long ago proven that the gas-impingement system of that rifle is imperfect because there’s not a firm connection for the operating system to move in one piece. The technology cannot be improved unless you remove gas impingement. And the Army knows that.”

    Scales is incorrigible; at every turn the evidence has worked against his position, but he doesn’t allow this to change his mind. Despite the fact that the M4 performed best overall in the IC Competition, despite the fact that the myth about the M4 requiring frequent cleaning was disproven long ago (indeed, this blogger’s mechanically stock Colt 6920 hasn’t been cleaned or lubed in over two thousand rounds, and still works just fine – although its action spring will need to be replaced soon), despite the fact that numerous anecdotes support the combat effectiveness and reliability of the M4, Scales will not change his mind.

    Certainly, I don’t expect this article to do what all the evidence has not, but I do feel it is necessary from time to time to address this sort of sensationalism. The Washington Times article essentially rides on the back of the above quotes from Scales, so it is his arguments, past and present, that I will comment on.

    Scales asserts the common belief that the direct impingement gas system of the AR-15 (and by extension, the M4 Carbine) is its fatal flaw; that a truly reliable rifle must have an operating rod to prevent gas fouling from entering the action of the weapon.

    While it’s true that the AR-15-type direct impingement system does introduce propellant gases into the action, it is not true that these gases impede the rifle’s function or cause the rifle to fail when hot. Andrew Tuohy of VuurwapenBlog covers the reasons for this in one of the videos on the VuurwapenBlog YouTube channel:

    The truth of Andrew’s words is borne out by the M4 Carbine’s excellent performance in the Individual Carbine competition, where it achieved the highest reliability rate in the two most serious categories of malfunctions, and the second-highest reliability rate in the least serious category. The Carbine’s high reliability contributed in large part to the cancellation of the IC competition, and the continuation of the M4 Carbine upgrade program that Scales is lambasting.

    In combat, the M4 Carbine has proven very reliable when properly maintained. “Maintenance” here does not mean “cleaning”, but the timely replacement of components before they wear out, of the kind that should be performed on all rifles. Simply, it is not possible to make a spring that does not wear out, or a stressed component that does not break. Further, it may be that the fouling myth has an actual detrimental affect on rifle reliability: If soldiers are attributing malfunctions of their weapon to carbon fouling, they may not be considering the wear their parts are experiencing, and they may ignore the most likely explanation: That their rifle needs maintenance.

    This explains why nowhere in the M4A1+ solicitation is there a request for operating rod upgrades. The M4 doesn’t need that, and the Army knows it. Why, then, does Maj. Gen. Scales think this is an “admission of guilt” by the Army?

    In truth, the M4A1+ upgrades seek to address some of the aging components of the system. The Knight’s accessory rail that was once so transformative for the M4 Carbine is now heavy and antiquated compared to newer rail systems. The M4A1’s trigger is famously “GI heavy” and the Army is seeking to incorporate an improved trigger that would facilitate more precision from the shooter while reducing fatigue. Other improvements, such as low profile gas blocks, higher quality barrels, better flash hiders, back up iron sights, etc. all would bring the military M4 in line with civilian developments, while not requiring replacement of existing rifles.

    None of these improvements involve the addition of the superfluous operating rod that Scales loves so well. All involve applying innovations that have been made in the last decade or so, and none yet mentioned are bug fixes. None “prove” the M4 is a fatally flawed weapon.

    What do soldiers think about the M4? A third-party study conducted by the CNA Corporation showed that among soldiers who had used the M4 Carbine in combat the weapon had a 90% approval rating, the highest of any of the basic infantry small arms (including also the M9, M249, and M16). The M4 and the M16 also had the lowest stoppage rate of all four weapons, both experiencing stoppages at less than two-thirds the rate of the operating-rod-driven M249. Further, users of the M4 told CNA that when the M4 had a malfunction it negatively affected their ability to fight the least, out of the four weapons. Overall, the M4 was the weapon in which combat infantrymen had the most confidence that it would go “bang” every time.

    So why does the M4’s reputation not reflect its performance? Part of the reason, and something I cannot speak to, is the issue of unit-level maintenance. Anecdotes reflect that some units have problems maintaining their weapons, even in dramatic ways; this is not something I can go into further, beyond a simple mention. However, another part of the reason is surely the incentive that some companies have to discredit the M4, or to portray it as a rifle that needs intensive maintenance. Obviously, a company selling an operating-rod rifle has an incentive to portray their product as superior, but also lubrication and cleaning products manufacturers have their own incentives to tell their customers to use their products more often.

    Beyond this, the M4 is a very reliable, very inexpensive, very adaptable weapon, and as such it is a very poor vehicle for government pork projects. There is therefore another incentive for tarnishing the rifle’s reputation: One of lobbyists and politicians to portray the rifle as needing replacement (see editorials claiming the M4 is too antiquated, despite the rifle’s development being completed in 1994, and it being in continuous production since then).

    All of these forces have battered the M4’s reputation, so it’s therefore very telling that the rifle is the foundation for the Army’s next generation of infantry weapons (what will come of the Carbine improvement program), and that it enjoys such a high approval rating.

    This context allows us to see Maj. Gen. Scales for what he is: A lobbyist. The “fatal flaw” of the M4 Carbine is not his only hobbyhorse; he has also written about the Army’s need to adopt such technologies as “cell phones”, “networked helmet cams”, and “people sniffers”. On this last, WeaponsMan writes:

    [H]e’s also showing a remarkable ignorance of the technical history of the People Sniffer (.pdf), Projects Muscle Shoals (.pdf, in-progress whitewash), Igloo White, and all those Macnamara Line developments. Those things were all costly failures. [emphasis mine]

    It is conceivable that Scales is not ignorant of this history, and is in fact counting on these sorts of costly projects to make money for his clients. I have already hyperlinked to the guest post written by Terence Nelan for Tamara Keel’s blog, a relevant excerpt of which is reproduced below:

    Back in 2008, he was the president of a consulting company named Colgen, which described itself somewhat immodestly as “America’s Premier Landpower Advocate.”   The site is no longer available, unless you go dig for it at (Link:

    On the site back in 2008, Colgen’s business was to assist “landpower Services in creating future warfighting doctrine and operational concepts” and it “translates these concepts into useful strategies and actions for industry, the media, and the congressional and executive branches of government.”
    Colgen’s “products targeted to these marketing elements including: media commentary, congressional testimony, advice to the executive branch, published works, seminars and conferences.”  [emphasis mine] Colgen’s “growing list of satisfied clients” includes defense contractors such as General Dynamics and Lockheed Martin.

    Note that Colgen clearly states that published works are a marketing product.

    One product that Scales pushed as late as 2010 is Heckler and Koch’s XM8 rifle, an ironic suggestion given the recent controversy surrounding the rifle upon which the XM8’s design was based, the G36 used by the German Bundeswehr. If Maj. Gen. Scales had had his way, the United States Army could well have been caught up in the storm currently surrounding the Bundeswehr and Heckler and Koch.

    The Washington Times is happy to accept Scales’ opinion as fact, and the video embedded in their article presents their correspondence with the Maj. Gen. as them “uncovering” the secret flawed nature of the M4. I am no more of a journalist than any other blogger, but simply parroting the words of a defense lobbyist does not strike me as the most honest or diligent journalistic practice.

    No rifle is perfect, and the M4 isn’t an exception. However, it is not the failure it has been portrayed to be by some. Rifles designed to replace it virtually without exception offer no significant improvements, and generally speaking are heavier and more expensive. The M4 offers a substantial improvement in adaptability versus older generations of rifles, and competes successfully with newer, purpose-designed modular weapons. While the M4 does not incorporate every inherent enhancement for reliability, it offers a major advantage in being one of the most well-understood systems available, which pays dividends in practical reliability. Until the paradigm shifts and the M4 is made truly obsolete, it will continue to hold its own.

    Nathaniel F

    Nathaniel is a history enthusiast and firearms hobbyist whose primary interest lies in military small arms technological developments beginning with the smokeless powder era. He can be reached via email at [email protected]