"Just because you're interested in what's best for the machine, doesn't mean the machine's interested in what's best for you."
Gun Lubricant History: The Cold War & CLP
The Cold War Pentagon: Home to many ideas inspired by potential Great Power wars, fielded in conditions that were anything but.
Industrial War: The One-Size-Fits-All Cold War DoD Machine
In order to understand why the military adopted CLP (Cleaner, Lubricant, Protectant), and why it's so common to see amongst civilian shooters today, it's important to understand the environment in which it emerged. In exploring this, it becomes much more understandable how LSA and the critical importance of grease in general for weapons reliability became lost to the shooting world.
As the war in Vietnam wound down, planners at the Department of Defense took the opportunity to get away from messy counter-insurgency warfare to focus on something they were much more comfortable with: industrialized warfare between great powers.
One of the key problems in 'Industrial Warfare', as well as competitive advantages, is logistics on a massive scale. To quote Omar Bradley, "Amateurs talk strategy; professionals talk logistics." Partly, logistics is the ability to get forces and supplies where they need to be, when they need to be there. However, another important aspect of this - which SecDef McNamara understood - was that efficiencies maximized across the entire DoD system are often how great powers defeat each other.
This was in evidence between the Nazis and the USSR - German tanks and other weapons were often elegant, complex, and high quality. While these attributes were excellent advantages at the individual level, often providing greater combat life and combat capacity to each weapon system, they didn't provide sufficient advantages to overcome the Soviet approach. The Soviets relied on churning out vast quantities of much cheaper and quicker "good enough" weapons. And this approach, within that context, allowed them to absolutely steamroll the Germans, albeit with tremendous loss of life, but it was a sacrifice they were willing to make in abundance. What the USSR did not have an abundance of, however, was war materiel. And by pursuing efficiencies on the margins it yielded a crushing victory. At this massive scale, the USSR simply got more fighting capacity out of every pound of metal.
These Industrial Warfare understandings were part of the governing theory behind adopting the M-16, over the more expensive to produce and field M-14. It's easy to forget in the shadow of Vietnam - the war we actually did experience - that the Pentagon spent that period largely focused on a potential but existential war with the USSR. While it thankfully never materialized, under that planning certain assumptions were made, and the powers at the time expected the US would maintain ongoing industrial capacity during a major war. Part of this included planning on not only being able to ramp up production of the substantially cheaper and easier to produce M-16 on a massive scale, but also being able to easily field cheap replacement M-16s when soldiers needed worn or broken parts replaced. A notable opposite to this approach are the Swiss, whose infantry are renowned for their marksmanship proficiencies. They expected to have zero industrial re-supply capacity in the event of an invasion. Understanding this, they maximized what they had in peacetime, and issued their soldiers the exceptionally high-quality SIG SG rifles, so that they wouldn't need to be replaced to begin with.
Soviet PPSh-41, designed to be extremely cheap and mass-produced, relying on simple machining and as many stamped parts as possible. Fewer labor hours and minimal material allowed the USSR to produce massive numbers of lower-quality but 'good enough' guns to win the war.
It's difficult to overstate the impact that WWII and Industrial Warfare theory had on the daily realities and culture of the Pentagon - these modes of thinking became so dominant that whole generations have passed through the DoD without encountering anything different. With the exception of the special operations community, "Industrial Warfare" theory in planning and procurement has been absolutely dominant from the Civil War to this very day in the DoD. Part of its core, foundational concepts emphasize uniformity of war materiel, working well enough, while maximizing efficiencies. This was pioneered by the US during the Civil War, and is how countries win on the margins against near-peers. The survival imperative of uniformity is critical - it minimizes the amount of logistical complications, saves money, and tends to maximize fighting capacities at the massive scale.
Stalin - a living embodiment of Industrial War theory. Centralized, ruthless, and entirely indifferent to individual survival.
A very severe consequence of this theory of warfare, however, is that it simply does not prize individual survival. It prizes system survival, which benefits from efficiencies on the margins, lowering individual capacity while increasing overall numbers of weapon systems. It sacrifices quality for quantity, because, as Stalin noted, quantity has a quality all its own.
This mentality is in marked contrast to the cultural norms of the special operations community, and is largely why the culture, training, and operational realities of Special Operations Forces (SOF) often reject much of the larger DoD norms and culture as a whole. While WWII and winning wars against near-peer great powers like the Soviets may have required winning wars on the margins, Special Operations doesn't win on the margin - SOF units win by being the most effective, highest quality elements on the field. SOF often accomplishes much more - often with much less in the long run - by leveraging the advantages of extreme quality, and developing small-unit cultural norms which prize individual creativity, initiative, and focusing on 'what works best', over uniformity and mass. This is a substantial difference in worldviews, and the culture clash regularly causes friction at the individual and operational levels between Big DoD and SOF. But, each has its own way of doing things rooted in their own warfighting experiences. And importantly, each has capabilities to win conflicts the other just doesn't have.
These experiences, however, are also explicitly why SOF has their own independent procurement systems, which focus on rapid evaluation and acquisition of high quality or specialty items. This is quite the opposite of the broader Pentagon, which tends to be slow and methodical during procurement processes, while focusing on factors such as cost efficiencies and massive scalability. Big DoD priorities often result in 'good enough' equipment optimized for massive war. (What's particularly bizarre is when this thinking is mixed, procuring ultra-high end weapons while forcing them into roles they're ill-suited for and that may wear them out quicker, such as killing the A-10 Warthog to have the F-35 do the Close Air Support job). What is unarguable in all of this, for the individual warfighter, having a 'good enough' gun issued under Industrial War theory wear out at the wrong time, or be insufficient for the "small war" you have, is that it has routinely proven lethal. This has been true from the Indian Wars - where units were issued re-fitted Civil War single-shots, in the face of Native forces using high quality repeating Henry and Winchester rifles - to contemporary Afghanistan, where the 5.56 round is often found to not have the ballistics needed in long, open, and often mountainous terrain. It's a lesson that continues to be repeated every generation. And toward the end of the Vietnam War, Industrial War theory was absolutely dominant in the Pentagon's planning and procurement processes - and this is the environment CLP emerged in.
One Fluid to Rule Them All
CLP emerged in an environment where the dominant institutional culture and worldview simply did not prize individual survival, but rather emphasized efficiencies at the margins across the entire DoD, focused on defeating the massive Red Army. Equipment had to work 'well enough' in a culture that largely ignored the consistent, daily realities of fighting small, messy wars, focusing instead on The Big What If. In 1971, somebody, somewhere in that Big DoD Cold War machine took Industrial Warfare theory to another extreme, and got the idea that they could cut out several different logistical tails in one magnificent swoop, if they could just find one weapons fluid to clean, lubricate, and protect at the same time. Never mind if it wasn't the best way to keep an individual gun running. It just had to be one thing that could do everything 'well enough', while cutting costs on the grand scale.
What began the journey of "CLP" was Purchase Description 48, or PD-48, in 1971. When one googles this, it is often found referenced accompanying claims of it being some sort of technological hurdle, and being referred to as the "Impossible Specification". However, when actually digging into the subsequent Military Specification, MIL-PRF-63460, the actual performance demands simply bear no evidence for it being difficult to accomplish - or of it being a good idea. Especially if the task is to keep an M-16 running with maximum reliability and longevity.
Under "industrialized war" theory, cheap products that work "well enough" are prized over highest quality. Here, Sailors and Marines clean and lubricate M-9s with CLP.
The purchase description sought to eliminate several oils and solvents in the inventory by having one fluid be able to lubricate (in what looks on first glance to be a very wide range of temperatures), as well as clean fouling deposits and prevent corrosion, all at once. Notably, it did have very stringent low-temperature demands as well. However, instead of using specialized tools for these jobs, this planner, in effect, wanted the firearm maintenance equivalent of issuing just one uniform to an Infantryman to serve as PT, wet weather, and battle uniform anywhere from the -50°F temperatures of Ft Wainwright, Alaska, to 120°F in Iraq. You can create create fluids that will indeed clean, lubricate, and protect a gun without any great difficulty, but by adding extreme temperature ranges and cleaning demands, it creates bad compromises that invariably cause reliability and longevity to suffer, in one way or another, usually by losing valuable boundary lubricants or work-life endurance. At the individual level, the best approach for lubricant is to optimize for standard and high-heat temperatures, and have a second lubricant optimized for cold weather operations. In failing do to this, you lose important benefits.
With CLP specifically, however, when one looks at the actual detailed specifications inside MIL-PRF-63460 from an engineering perspective, something stands out that should be alarming to someone familiar with the operating realities of the M-16 and its variants: the temperature range is only required to go up to 160°F.
The Bolt Carrier Group of AR-style direct impingement systems gets exposed to flash temperatures of 400-1000F, depending on location, with every shot, that are incredibly brutal on lubricant.
To put this in perspective, in 100°F weather the surface temperatures of a black car resting with the engine off can easily exceed 170°F. And these rifles are black - generally fielded in the desert sun, during our present era. Also, while not universal, and not the only issue at hand, this does partially account for reports of military weapons simply 'drying out' on duty, needing to be regularly and consistently relubricated, even without firing.
Vastly more dangerous for reliability, however, is that the actual temperatures of the gasses flashing over key friction surfaces of the M-16/M-4's bolt carrier group (BCG) range from 400°F to 1000°F. This temperature difference comes from many variables, including barrel and gas tube length differences between a rifle or carbine system, and the distance of a particular part of the BCG from the gas tube's exit port. Inside the barrel itself, the temperatures of these gasses are roughly 1500°F at the gas port, and with the addition of oxygen after escaping the muzzle can flash to well over 2000°F (also the origin of "first-round pop" with suppressors). The gasses diverted into the gas tube rapidly cool, but are still in the vicinity of 1000°F as they exit the gas tube to hit the gas key of the BCG.
While it's a very short spike of temperature, which can be cut in half by the time it actually reaches the internal gas chamber within the BCG to pressurize it and cycle the weapon, those low temperatures are still over 200 degrees hotter than the "Mil-spec" standards CLP are required to withstand.
One key point to note is just how fast these flashes of temperature are - because they're so fast, and because of their locations, few people have been in a position to physically perceive the heat. Because of this, it's largely not commonly understood just how hot these gasses are. But their short duration is also why barrels and other parts don't rapidly reach the temperatures of these gasses - there's just not a steady-enough constant application of energy, unless full-auto fire begins exceeding roughly 100 straight rounds.
At that point, barrels can become hot enough to partially melt and destabilize lead-core bullets of .223/5.56 diameter, and after several hundred rounds will experience a gas tube failure, as in the video at right, or the barrel itself will burst, between 1600°F-1700°F.
However, while these flash temperatures of 1000°F gas take continual fire to heat the relatively large masses of metal in barrels and BCGs, every jet of gas will flash away tiny amounts of lubricant with every shot - especially with improperly selected lubricants. The more poorly the lubricant is matched to this system, the faster that flash evaporation and burning off occurs. Proper lubricants may have little to none.
But it is this reality behind why it's such a common experience for those in the military to have their M-16 or M-4 go dry of lubricant very early into a firefight. The more intense the cadence of fire, the quicker this happens with milspec CLPs at the 160°F standard. A severe problem historically, however, has been that malfunctions often get misdiagnosed as the problem of a specific weapon, rather than on lack of lubricant. Or more appropriately, historically they've not been diagnosed as having the excessive levels of friction these weapons are malfunctioning under.
Full-Auto Failure Test: Notice weapon appears to have been heavily lubricated - lube burn-off smoke appears for first several mags, then declines, then smoke from plastic handguards appears. Also note that lab sterility allowed for MUCH more fire than soldiers experienced in the presence of real-world friction contaminant at the Battle of Wanat.
As if this immediate life-and-death reality of CLP burn-off wasn't troubling enough, another potentially severe long-term problem is the presence of PTFE, or Teflon, in CLPs. Teflon is used as a boundary lubricant, laying over surface metals, while the liquid carrier is meant to provide hydrodynamic lubrication, corrosion protection, and cleaning capacity. However, in an M-16 variant, these light liquids not only have difficulty reaching the hydrodynamic lubrication regime, their weight and the violence of the action thins and spreads them out. Combined, the intense jet of hot gasses can also quickly evaporate them off - while 'pyrolisizing' the Teflon, heating it or burning it, releasing its byproducts. There is substantial evidence, discussed partially in the Hidden Hazards section, that Teflon begins producing dangerous, bioaccumulative carcinogens, neurotoxins, and endocrine disruptors at temperatures as low as 325°F. And with an M-16, M-4, or AR variant lubricated with CLPs using Teflon, not only are these gasses and toxins being produced, they're getting blown back into your face with every shot.
Those who risk their lives at work have a noted tendency to prefer the best, most effectively optimized tool for any given job at hand.
On a final note, it's worth pointing out that PD-48 seems to have sought to solve a problem that nobody on the using end had. LSA was a great lubricant that kept M-16s running, with superior longevity and ability to stay put both during firing and in general. Notably, even field expedient solvents like kerosene or diesel can clean better than CLPs. As with so many Cold War programs, those pushing it seem to have sought to produce efficiencies at the grand scale, rather than focus on maximizing the fighting capacity of every individual warfighter.
We hope this information has been interesting, and helpful to you in answering questions many of us have had. In providing it, we chose to so heavily emphasize and discuss the theoretical and cultural environment CLPs originated in, for this critically important reason: many of the things the shooting world considers "normal" are only that way because of decades of Pentagon influence on the culture of the shooting community, by way of having tens of millions of Americans pass through the service.
In effect, when millions of people go into the military at age 18, they internalize military norms, and bring them back out into the broader shooting community in such high volume that it can change the norms and expectations of the civilian shooting culture as a whole, especially over decades. Add in the deeply ingrained sense of right/wrong their training may have instilled in them, and it can be incredibly powerful - both in good ways, and in dangerous ways simply unknown to them, for no cause of their own. In this case, CLPs may seem 'normal' to many of us, but from an engineering perspective, they're a middling compromise that will cause machines to wear out quicker and be less reliable in the process. Especially over using specialized, quality lubricants engineered specifically for guns. As anyone with military experience understands, "you are not an individual" in the military. And what is best for the individual under Industrial Warfare theory is not always what is best for the system. But that system, even if you haven't lived through it, has likely altered your perception of what 'normal' is for guns.
Conclusion: How "gun oil" became normal
Beginning with the introduction of the M-16 in 1965, the military removed itself from universally accepted lubrication norms of using grease in unsealed, sliding systems, and switched to using oils. These oils included haphazard field expedients, experimentals, and directly issuing the VV-L-800 light weapons oil. While there was a brief period of using a light grease, LSA, the bottles themselves were marked 'oil'. And CLP itself is a multi-component oil.
In essence, for nearly 50 years, those having cycled through the US military have understood themselves to be using a "gun oil". It's worth noting that this entire period covers the use of the M-16 and its subsequent variants - a period plagued with reported reliability problems that do indeed continue to the present day to varying degrees. Problems that, when addressed with proper lubrication, largely cease. This is in notable contrast to the 20 years before the M-16, and the incredible reliability of weapons using greases.
This is the root of the Great Disconnect - how we went from grease, which is the proper lubricant for unsealed, sliding systems - to oils. With the military making the choices it did, combined with tens of millions of people cycling through the military, oils simply became culturally normal, even if they're clearly inferior, inappropriate lubricants for these machines.