Who uses WD-40?
- Thread starter KUHIO
- Start date
In all seriousness I must warn all posters that WD-40 is considered a a highly dangerous product by the EPA. It will desroy any gun it is sprayed upon within .0001 milliseconds. In most instances the gun will immediately congeal into a pile of quivering gelatinous mass. This mass can only be disposed of according to EPA reg 37-85-001, paragraph 3-887-25.0. Additionally any container of WD-40 stored within 300 meters of a firearm not protected by lead shielding meeting the standards of the Dept of Com. reg. 1574.2284, paragraph 68-84, sub paragraph 65-87-410 will suffer a gradual deteriation over a period 29 minutes into an inert metallic lump. WD-40 will also cause your children to go sterile if they read the label. In addition WD-40 is known to cause crop failures, locusts and famine in parts of the Horn of Africa. Historically there is evidence that WD-40 caused Atlantis to sink under the Atlantic Ocean and may have motivated the Romans to crucify Jesus. Use it at your own risk of apocalypse. A whole bunch of you keyboard cowboys are full of it.
redwing 40
New member
When the temperature drops way down and that gas engine will hardly start just give the breather a shot of WD40. WD40 is the best starting fluid you can find.I know many shooters who have used it for years on firearms with no problems.
This thread needs another post!!
I have used it to clean semi gungy machine tools.Bridgeport,lathe,grinder.Not drown,but wipe-down.
It makes a darn good drill/tap fluid for aluminum
I won't argue with the folks who have found something better,but I used it in the past quite a bit.We discovered don't spray it on the gun.Something about the propellant foaming a little and then a rust problem.
Spray some on a rag.Then,a wipedown after handling worked to remove fingerprints.Some folks have rusty fingerprints.I think the clean-off part is good.
For a rust preservative,Old School RIG works.A Rig-rag,kept clean in a jar or tobacco tin to lay down a thin layer.Also nice,a rig treated piece of shearing sheepskin.
there is a very pure lanolin that is used on gages.I seal rust blue with beeswax and terpentine.I lube my AR and other semis with a rubbed thin coat of Castrol Blue Synthetic auto grease.I keep 16 gal barrel of solvent in the garage.I have been known to fill a touch up paint spray gun with laquer thinner to flush out and degrease.No chlorine.
My old South Bend lathe manual recommended Vaseline disolved in naptha for anti-rust machine preservative(circa1941)
I have used it to clean semi gungy machine tools.Bridgeport,lathe,grinder.Not drown,but wipe-down.
It makes a darn good drill/tap fluid for aluminum
I won't argue with the folks who have found something better,but I used it in the past quite a bit.We discovered don't spray it on the gun.Something about the propellant foaming a little and then a rust problem.
Spray some on a rag.Then,a wipedown after handling worked to remove fingerprints.Some folks have rusty fingerprints.I think the clean-off part is good.
For a rust preservative,Old School RIG works.A Rig-rag,kept clean in a jar or tobacco tin to lay down a thin layer.Also nice,a rig treated piece of shearing sheepskin.
there is a very pure lanolin that is used on gages.I seal rust blue with beeswax and terpentine.I lube my AR and other semis with a rubbed thin coat of Castrol Blue Synthetic auto grease.I keep 16 gal barrel of solvent in the garage.I have been known to fill a touch up paint spray gun with laquer thinner to flush out and degrease.No chlorine.
My old South Bend lathe manual recommended Vaseline disolved in naptha for anti-rust machine preservative(circa1941)
Can't vote, choice are too narrow. I will use it sometimes to loosen grit and grim when cleaning but I do not use it as the primary cleaner or lubricant.
I will use it as both in the field for quick cleanup especially on my shotguns when spending several days hunting. But when I get home - it is a powder solvent, copper solvent and clp.
I will use it as both in the field for quick cleanup especially on my shotguns when spending several days hunting. But when I get home - it is a powder solvent, copper solvent and clp.
armsmaster270
New member
Having 2 gallon jugs, 7 pints, 15 - 4oz bottles and 36 - .68oz bottles of Break Free I'll stick with it til about 30 years after I die.
I wandered into one of the best threads on this site here.
I guess I will keep my WD-40 away from my guns and my locks.
Dern,I did'nt know it could jam up moving parts or especially- inert primers!
Works great for getting jammed bolts off car parts though!
I pretty much use Hoppes brand stuff for the guns anyway.
I guess I will keep my WD-40 away from my guns and my locks.
Dern,I did'nt know it could jam up moving parts or especially- inert primers!
Works great for getting jammed bolts off car parts though!
I pretty much use Hoppes brand stuff for the guns anyway.
I got 36k miles out of a DID O-Ring chain (on a Triumph Speed Triple) by cleaning and lubing it with nothing other than WD-40. However, I had to apply WD-40 very frequently, usually about every 500 miles and much more frequently when I rode in wet weather. Chain failure/wear usually occurs when the O-rings wear out and allow dirt and moisture into the rollers. Dirt is probably the biggest culprit to O-ring wear. The wax or heavy motorcycle specific chain lubes seem to attract a lot of dirt and sand.
I don't consider WD-40 to be the end-all be-all of lubricants. Like Kroil, Liquid Wrench, (aerosol) white lithium grease, LPS, saBesto HHS2000 (from Wurth) (aerosol) silicone dry lube, Moly and graphite, I find it to be one of the "tools" available to me.
I have used WD-40 on firearms but only to clean the inside of a barrel. I think there are better product choices for lubricating firearms.
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I used WD-40 exclusively on my KLR650 chains. I would carry a small can with me and spritzed the chain each morning when I was on a long trip into the woods. I got ~20-25K on a chain. I also used Breakfree on occasion. I do not use WD-40 on fire arms as there are plenty of good inexpensive oils available, but a can of MC chain lube can run you $12-$18.
Funny, you find these WD-40 pro/con threads on the dual sport MC forums too. There are some that swear WD-40 will ruin a O-ring chain by dissolving the O-rings
Funny, you find these WD-40 pro/con threads on the dual sport MC forums too. There are some that swear WD-40 will ruin a O-ring chain by dissolving the O-rings
"Corrosion Block" Corrosion Block is a marine version of the aviation and
military's ACF-50.
You just cannot beat this stuff on firearms.
Research ACF-50 and see what I mean.
http://www.nocorrosion.com/corrosion-control.htm
military's ACF-50.
You just cannot beat this stuff on firearms.
Research ACF-50 and see what I mean.
http://www.nocorrosion.com/corrosion-control.htm
Simple test. Spray a bit of WD-40 into its own cap and let it sit. Check out the yellow goo that is left behind.
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Here is a great article on lubricants by well known gunsmith Grant Cunningham. http://www.grantcunningham.com/lubricants101.html
Lubrication 101
Introduction
Firearms enthusiasts are the targets (pardon the pun) of some of the most misleading advertisements regarding the proper lubrication of their guns. The purpose of this article is to give a background on basic lubrication concepts, the technology behind them, and some guidelines for selecting lubricants based on facts, not hype.
Before going further, let's make something perfectly clear: with a very few obvious exceptions, firearms lubrication isn't terribly difficult. Compared to many more common objects, guns just don't make big demands of their lubricants! That's right, firearms pose no actual "extreme" situations with which a lubricant must deal. There are thousands upon thousands of 100-year-old-plus guns out there that are functioning - just fine, thank you - on a diet of "3-in-1" oil.
However, that doesn't mean that there isn't something better! This article, it is hoped, will help you determine just what "better" means to you.
Let's start at the beginning...
Why lubricate something? First, to prevent wear and second, to promote a certain level of performance. To put it more clearly, what we're trying to do is to keep parts from rubbing directly on other parts, and to make the interaction of those parts as smooth as possible.
As it turns out, those polished surfaces that rub against each other aren't all that smooth. Looking through a microscope, even the most highly finished metal surface still looks like a forested hillside - with all kinds of huge voids, depressions, and valleys. Imagine, then, what happens when that surface meets the surface of it's companion part! Not only does the combination become difficult to move, but the tops of those trees get broken off - that's how wear starts at the microscopic level.
That's why we lubricate those surfaces. Lubrication works in a couple of ways: "hydrodynamic" and "boundary".
Hydrodynamic lubrication is essentially when the parts ride on the film of liquid (or semi-liquid) lubricant; the lubricant fills all of the voids, and the film itself serves as a buffer to keep the surfaces apart.
This works really well, except when a load is applied and the lubricant is squeezed out of it's space between the surfaces. When that happens, the surfaces grind together and wear. What if we added something to the mix - something that was a bit more "solid" than the lubricant, which wouldn't be easily squeezed out? Well, that's just what "boundary" lubrication entails - adding small pieces of more-solid material to serve as a physical separator between the surfaces, keeping them from tearing each other to pieces.
The solids that provide this service are known as "anti-wear" or "extreme pressure" (AW/EP) additives - solids of microscopic size that are mixed into a lubricant, in order to maintain a protective boundary (get it?) under load. "Moly", a generic term for several molydenum compounds, is one example; others include sulphur compunds, zinc, polytetrafluoroethylene (PTFE, aka 'teflon'), zinc diakyl dithiophosphate (ZDDP), phosphors, boron, antimony diakyl dithiocarbamate (and it's derivatives), and many more. Each of these has certain properties that the skilled tribologist (lubrication scientist) will balance to achieve the optimum lubricant for the application.
Regardless of the physical characteristics of the product, lubricants are a "package" - the primary lubricant plus boundary additives, thickeners (as in greases), and other things (tackifiers, pour point depressants, detergents...the list is endless and chock full of chemical names I can't begin to decipher!)
My exaggerated interpretation of the primary lubrication states.
All about grease
Grease is nothing more than thickened oil. That's it, folks - no mystery here! Grease is nothing more than oil which has been thickened with a "base" - that base being a metallic soap (lithium, aluminum, barium, calcium), or a non-soap alternative (bentone, polyurea.) Each of these bases have different characteristics, which are taken into account (along with the oils and additives) to produce a grease of the desired effectiveness.
Of course, each base has its own characteristics. Different bases will show different degrees of water resistance, cold weather performance, stability (the ability to resist oil separation under shear and mechanical operations), oxidation, and "reversability" - the ability of the base to re-absorb any oil that might have been separated.
Lithium is the most common base encountered; it's cheap, easily produced, and has enough good traits to make it a decent choice for all-around use. However, aluminum bases have several advantages: much better resistance to water (and acids and alkalis), better low-temperature performance, better stability, and dramatically increased reversability. Aluminum greases are typically a bit harder to find, and more costly, but their performance advantages can be pretty dramatic.
Finally, grease is graded in thickness by its NLGI number. Most grease you're familiar with is NLGI #2; smaller numbers mean less thickness. A grease rated at NLGI #00 is almost a liquid a room temperatures.
What makes for a good gun lube?
Firearms encounter intermittent high loads, interspersed with long periods of inaction. This means that the primary lubrication need isn't hydrodynamic - it's boundary. What, then, should we be looking for?
Start with a very good boundary lubrication package - that translates to lots of EP/AW additives. We need superb corrosion resistance, along with resistance to oxidation (don't want those lubricants thickening up.) We also need excellent water resistance and some ability to withstand mild acid and alkali exposure. Low temperature performance would be icing on the cake, and for a grease we want something that won't easily separate under load.
Physically, we need an oil to migrate. No, I don't mean to fly south for the winter! Migration is the ability of the lubricant to spread to surrounding and adjacent areas. For instance, let's say we're lubricating the shaft on which a hammer pivots; a lubricant with poor migration would just sit where we applied it, and would never get into the space between the hammer hole and the pivot. The net result would be a poorly lubed mechanism. A lube with good migration will succumb to capillary action and snake its way down into that small space, lubricating everything it comes into contact with.
Sounds like migration is just the cat's meow, right? Not always! For instance, that same migration that is so desirable on hammers and triggers isn't really good on autopistol slides; the lubricant tends to "run off", or migrates to the holster (or your clothes.) Ever wonder why your autoloader slide goes "dry" while in the holster? Lubricant migration! (What, you think it disappeared into thin air?)
What about greases - do we even need them? You bet! I use the General Rule of Lubrication: oil for rotating parts, grease for sliding parts that carry a load. In firearms, grease is most appropriate for any part interaction that has a scraping (aka "shear") type of action, and will be subjected to pressure or shock. What kinds of parts are we talking about? Slide rails, bolt carriers, and sears - especially double-action sears. (An example of a sliding part that should not be greased is the trigger bow of the 1911 pistol - it carries virtually no load, and is subject to almost no stress.)
That's a pretty good explanation of what we need - is there anything we should avoid? Of course - any product that contains chlorine compounds. These compounds, usually referred to as chlorinated esters, were used as boundary additives for many years. As boundary lubes they actually work pretty well; the problem is that they promote a phenomenon known as "stress corrosion cracking" (SCC). Essentially, SCC creates microscopic pits and cracks that, under heat and pressure, widen to become noticeable cracks - and sometimes, even broken parts!
(One major gun manufacturer actually had barrels fall off of their revolvers. An investigation ensued, and they found that the chlorinated esters used in their machining oils was causing stress cracking in barrel threads. When combined with the gun owners' use of cleaning and lube compounds containing chlorinated esters, the barrels simply sheared off at the weakest part - the threads. To this day, the company forbids any chlorine-carrying compounds on the manufacturing floor, to prevent a recurrence.)
What about "miracle products"?
Let's be clear: there are no "new", "revolutionary" lubricant products made for firearms. That's a flat statement, and it's intended to be. All of the lubricants, bases, and additives of suitable use are already well known to the lubricant industry. Specific combinations might be unique, but it's all been tried before - if not necessarily on guns.
There are several such products on the market right now that are simply a well-known boundary additive in a light carrier; at least one of them is a chlorinated ester! These things have been around a long time, and unless you didn't know better the products using them would indeed seem to be "revolutionary." Just remember: any new gun lube is going to be made up of readily available components, perhaps blended especially for the requirement, but will not be a "miracle". 'Nuff said!
Cut to the chase! What should I use?
Let's start with oil. Most people use oils that are way too heavy; thicker is not better! Use a relatively thin oil with the correct properties, and use it very sparingly - most "oil failures" I've seen have been from too much, rather than too little, oil.
Frankly, in terms of mechanical performance most oils "work"; some are better than others, but everything will make parts move for a while. What really gets most oils is lack of corrosion resistance - in a gun, corrosion is a bad thing! There have been lots of claims, but those people who have actually taken the time to run experiments to test corrosion on steel have found that the products with the greatest hype are often the worst at corrosion resistance. Not surprisingly, plain mineral oils, such as Rem Oil, score at the very bottom of the list.
Ironically, the product that scores at or very near the top of just about everyone's testing is also the most available, and the cheapest. It also has good migration, a good boundary lubrication package, is the right weight (thickness) for general firearms use, doesn't oxidize over long periods of storage, and is compatible with a wide range of metals and plastics. In addition, it is recommended by at least one real degreed firearms engineer! Just what is this miracle elixir??
Dexron-type Automatic Transmission Fluid (ATF). That's right, plain ol' ATF. The kind you get at every gas station, auto parts store, and even most convenience stores. Synthetic or regular, either will work just fine. (ATF does have a slight odor to it. If you find that objectionable, a decent alternative that is still readily available is "NyOil." Check your local auto parts store, in the aisle where they keep the miscellaneous lubricants and additives.)
What about grease? Remember that you should grease sliding parts that carry a load - slide rails, sears, and bolt carriers. Again, remember to start with your criteria: must have superb boundary lubricants (particularly when used on double-action mechanisms), preferably of aluminum base, good cold working characteristics, resistant to acids/alkalis and water (especially water), and preferably of a non-staining variety (black grease stains look awful on clothing!)
Except for the color, Brownell's Action Lube is superb - wonderful boundary lubricants (in fact, it is mostly composed of molybdenum compounds in a light grease base. It is great on action parts, and works well on slide rails - as long as you don't mind black stains. Yuck!
There is a better alternative for slides and bolts, but is unfortunately quite hard to get: Lubriplate "SFL" NLGI #0 grease. It is white, aluminum-based, low odor, has superb boundary lubricants, and is designed specifically for use in environments that encounter a huge temperature range. Unfortunately, the smallest quantity you can buy is a 35lb pail! (You may be able to get a small quantity from companies that make/supply/repair food service equipment, as it's one of the few greases approved for that use. Ask nicely.)
Lubriplate also makes SFL in heavier grades, which are more readily available in common cartridges. Finding the NLGI #1 is fairly easy, and I've had good luck with it, but really prefer the lighter grease - when I can get it! In either grade, this is such a superb product that it is worth searching out.
If you can't find it (and I wouldn't be surprised if you can't), Lubriplate also makes a similar product known as "SFO" grease. Also aluminum-based, it shares many of the same characteristics of the SFL grease, except for the extreme low temperature performance. (If you spend most of your time with a dog team in the Yukon, then it might be a problem. Just about anywhere else, it won't be.) The NLGI #0 weight comes in 14 oz. cartridges, and is far easier to find than the SFL #0. Check with bearing suppliers in your area; if they don't have it, they can probably get it fairly easily.
But what about......?
Everyone has their own little "secret". If it works, is there anything wrong with it? Let's find out...
Motor oils: Generally good boundary lubrication (particularly the Havoline formulations), but very poor corrosion resistance and poor resistance to open-air oxidation. In addition, their pour-point additives often contain benzene compounds, which aren't a good thing to have next to your skin on a regular basis! ATF is better on every count, even if it is a tad more expensive. (ATF is still 1/10 to 1/100th the cost of a specialty "gun oil"!)
Gear oils: Almost invariably too thick for the application. In addition, they contain tackifiers which gives them poor migration and lead to oxidization in open air, rendering them even more "sticky" - pretty much what you don't want! (Many folks use it on their slide rails because it's thicker and won't migrate easily; that's why we have grease, people!) If you really want a thicker oil with all the good characteristics we've covered, mix ATF and STP Oil Treatment in a 40/60 ratio. Far better than gear oil on every count.
WD-40: WD-40 was never meant to be a lubricant - it was designed as a moisture displacement agent. It's far too light for any load protection, has incredibly poor corrosion resistance, contains zero boundary lubricants, and rapidly oxidizes to form a sickly yellow varnish (hint: this is not good for delicate internal lockwork.) There are those who will defend this stuff vehemently, but then again you can still find people who think smokeless powder is a passing fad.
Automotive motor oil additives: Usually a boundary additive in some sort of light mineral oil carrier, they all lack corrosion protection and often oxidize rapidly; some have poor migration characteristics and rely on the oil to which they'll be added to provide those things. There are better and cheaper alternatives; save your money.
Silicone spray: Right up there with WD-40, but at least it'll shed water while your parts grind themselves into little shavings!
Graphite: (sprays, powders) Graphite is a crystalline product which is actually very slightly abrasive. It offers no appreciable benefit other than being dry; a lube with a good boundary lubricant package can be wiped dry to the touch and still provide better lubrication and protection than graphite.
Finally, note that the foregoing is a layman's understanding of lubrication technology. I don't pretend to be an expert, just a well-informed amateur hoping to disseminate some arcane knowledge. Use at your own risk!
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For all defending WD-40 as anything more than a water displacer, please, do not let the facts of lubrication physics vs. WD-40's formulation get in your way. Perhaps we can discuss if the Earth is really round next.
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Here is a great article on lubricants by well known gunsmith Grant Cunningham. http://www.grantcunningham.com/lubricants101.html
Lubrication 101
Introduction
Firearms enthusiasts are the targets (pardon the pun) of some of the most misleading advertisements regarding the proper lubrication of their guns. The purpose of this article is to give a background on basic lubrication concepts, the technology behind them, and some guidelines for selecting lubricants based on facts, not hype.
Before going further, let's make something perfectly clear: with a very few obvious exceptions, firearms lubrication isn't terribly difficult. Compared to many more common objects, guns just don't make big demands of their lubricants! That's right, firearms pose no actual "extreme" situations with which a lubricant must deal. There are thousands upon thousands of 100-year-old-plus guns out there that are functioning - just fine, thank you - on a diet of "3-in-1" oil.
However, that doesn't mean that there isn't something better! This article, it is hoped, will help you determine just what "better" means to you.
Let's start at the beginning...
Why lubricate something? First, to prevent wear and second, to promote a certain level of performance. To put it more clearly, what we're trying to do is to keep parts from rubbing directly on other parts, and to make the interaction of those parts as smooth as possible.
As it turns out, those polished surfaces that rub against each other aren't all that smooth. Looking through a microscope, even the most highly finished metal surface still looks like a forested hillside - with all kinds of huge voids, depressions, and valleys. Imagine, then, what happens when that surface meets the surface of it's companion part! Not only does the combination become difficult to move, but the tops of those trees get broken off - that's how wear starts at the microscopic level.
That's why we lubricate those surfaces. Lubrication works in a couple of ways: "hydrodynamic" and "boundary".
Hydrodynamic lubrication is essentially when the parts ride on the film of liquid (or semi-liquid) lubricant; the lubricant fills all of the voids, and the film itself serves as a buffer to keep the surfaces apart.
This works really well, except when a load is applied and the lubricant is squeezed out of it's space between the surfaces. When that happens, the surfaces grind together and wear. What if we added something to the mix - something that was a bit more "solid" than the lubricant, which wouldn't be easily squeezed out? Well, that's just what "boundary" lubrication entails - adding small pieces of more-solid material to serve as a physical separator between the surfaces, keeping them from tearing each other to pieces.
The solids that provide this service are known as "anti-wear" or "extreme pressure" (AW/EP) additives - solids of microscopic size that are mixed into a lubricant, in order to maintain a protective boundary (get it?) under load. "Moly", a generic term for several molydenum compounds, is one example; others include sulphur compunds, zinc, polytetrafluoroethylene (PTFE, aka 'teflon'), zinc diakyl dithiophosphate (ZDDP), phosphors, boron, antimony diakyl dithiocarbamate (and it's derivatives), and many more. Each of these has certain properties that the skilled tribologist (lubrication scientist) will balance to achieve the optimum lubricant for the application.
Regardless of the physical characteristics of the product, lubricants are a "package" - the primary lubricant plus boundary additives, thickeners (as in greases), and other things (tackifiers, pour point depressants, detergents...the list is endless and chock full of chemical names I can't begin to decipher!)
My exaggerated interpretation of the primary lubrication states.
All about grease
Grease is nothing more than thickened oil. That's it, folks - no mystery here! Grease is nothing more than oil which has been thickened with a "base" - that base being a metallic soap (lithium, aluminum, barium, calcium), or a non-soap alternative (bentone, polyurea.) Each of these bases have different characteristics, which are taken into account (along with the oils and additives) to produce a grease of the desired effectiveness.
Of course, each base has its own characteristics. Different bases will show different degrees of water resistance, cold weather performance, stability (the ability to resist oil separation under shear and mechanical operations), oxidation, and "reversability" - the ability of the base to re-absorb any oil that might have been separated.
Lithium is the most common base encountered; it's cheap, easily produced, and has enough good traits to make it a decent choice for all-around use. However, aluminum bases have several advantages: much better resistance to water (and acids and alkalis), better low-temperature performance, better stability, and dramatically increased reversability. Aluminum greases are typically a bit harder to find, and more costly, but their performance advantages can be pretty dramatic.
Finally, grease is graded in thickness by its NLGI number. Most grease you're familiar with is NLGI #2; smaller numbers mean less thickness. A grease rated at NLGI #00 is almost a liquid a room temperatures.
What makes for a good gun lube?
Firearms encounter intermittent high loads, interspersed with long periods of inaction. This means that the primary lubrication need isn't hydrodynamic - it's boundary. What, then, should we be looking for?
Start with a very good boundary lubrication package - that translates to lots of EP/AW additives. We need superb corrosion resistance, along with resistance to oxidation (don't want those lubricants thickening up.) We also need excellent water resistance and some ability to withstand mild acid and alkali exposure. Low temperature performance would be icing on the cake, and for a grease we want something that won't easily separate under load.
Physically, we need an oil to migrate. No, I don't mean to fly south for the winter! Migration is the ability of the lubricant to spread to surrounding and adjacent areas. For instance, let's say we're lubricating the shaft on which a hammer pivots; a lubricant with poor migration would just sit where we applied it, and would never get into the space between the hammer hole and the pivot. The net result would be a poorly lubed mechanism. A lube with good migration will succumb to capillary action and snake its way down into that small space, lubricating everything it comes into contact with.
Sounds like migration is just the cat's meow, right? Not always! For instance, that same migration that is so desirable on hammers and triggers isn't really good on autopistol slides; the lubricant tends to "run off", or migrates to the holster (or your clothes.) Ever wonder why your autoloader slide goes "dry" while in the holster? Lubricant migration! (What, you think it disappeared into thin air?)
What about greases - do we even need them? You bet! I use the General Rule of Lubrication: oil for rotating parts, grease for sliding parts that carry a load. In firearms, grease is most appropriate for any part interaction that has a scraping (aka "shear") type of action, and will be subjected to pressure or shock. What kinds of parts are we talking about? Slide rails, bolt carriers, and sears - especially double-action sears. (An example of a sliding part that should not be greased is the trigger bow of the 1911 pistol - it carries virtually no load, and is subject to almost no stress.)
That's a pretty good explanation of what we need - is there anything we should avoid? Of course - any product that contains chlorine compounds. These compounds, usually referred to as chlorinated esters, were used as boundary additives for many years. As boundary lubes they actually work pretty well; the problem is that they promote a phenomenon known as "stress corrosion cracking" (SCC). Essentially, SCC creates microscopic pits and cracks that, under heat and pressure, widen to become noticeable cracks - and sometimes, even broken parts!
(One major gun manufacturer actually had barrels fall off of their revolvers. An investigation ensued, and they found that the chlorinated esters used in their machining oils was causing stress cracking in barrel threads. When combined with the gun owners' use of cleaning and lube compounds containing chlorinated esters, the barrels simply sheared off at the weakest part - the threads. To this day, the company forbids any chlorine-carrying compounds on the manufacturing floor, to prevent a recurrence.)
What about "miracle products"?
Let's be clear: there are no "new", "revolutionary" lubricant products made for firearms. That's a flat statement, and it's intended to be. All of the lubricants, bases, and additives of suitable use are already well known to the lubricant industry. Specific combinations might be unique, but it's all been tried before - if not necessarily on guns.
There are several such products on the market right now that are simply a well-known boundary additive in a light carrier; at least one of them is a chlorinated ester! These things have been around a long time, and unless you didn't know better the products using them would indeed seem to be "revolutionary." Just remember: any new gun lube is going to be made up of readily available components, perhaps blended especially for the requirement, but will not be a "miracle". 'Nuff said!
Cut to the chase! What should I use?
Let's start with oil. Most people use oils that are way too heavy; thicker is not better! Use a relatively thin oil with the correct properties, and use it very sparingly - most "oil failures" I've seen have been from too much, rather than too little, oil.
Frankly, in terms of mechanical performance most oils "work"; some are better than others, but everything will make parts move for a while. What really gets most oils is lack of corrosion resistance - in a gun, corrosion is a bad thing! There have been lots of claims, but those people who have actually taken the time to run experiments to test corrosion on steel have found that the products with the greatest hype are often the worst at corrosion resistance. Not surprisingly, plain mineral oils, such as Rem Oil, score at the very bottom of the list.
Ironically, the product that scores at or very near the top of just about everyone's testing is also the most available, and the cheapest. It also has good migration, a good boundary lubrication package, is the right weight (thickness) for general firearms use, doesn't oxidize over long periods of storage, and is compatible with a wide range of metals and plastics. In addition, it is recommended by at least one real degreed firearms engineer! Just what is this miracle elixir??
Dexron-type Automatic Transmission Fluid (ATF). That's right, plain ol' ATF. The kind you get at every gas station, auto parts store, and even most convenience stores. Synthetic or regular, either will work just fine. (ATF does have a slight odor to it. If you find that objectionable, a decent alternative that is still readily available is "NyOil." Check your local auto parts store, in the aisle where they keep the miscellaneous lubricants and additives.)
What about grease? Remember that you should grease sliding parts that carry a load - slide rails, sears, and bolt carriers. Again, remember to start with your criteria: must have superb boundary lubricants (particularly when used on double-action mechanisms), preferably of aluminum base, good cold working characteristics, resistant to acids/alkalis and water (especially water), and preferably of a non-staining variety (black grease stains look awful on clothing!)
Except for the color, Brownell's Action Lube is superb - wonderful boundary lubricants (in fact, it is mostly composed of molybdenum compounds in a light grease base. It is great on action parts, and works well on slide rails - as long as you don't mind black stains. Yuck!
There is a better alternative for slides and bolts, but is unfortunately quite hard to get: Lubriplate "SFL" NLGI #0 grease. It is white, aluminum-based, low odor, has superb boundary lubricants, and is designed specifically for use in environments that encounter a huge temperature range. Unfortunately, the smallest quantity you can buy is a 35lb pail! (You may be able to get a small quantity from companies that make/supply/repair food service equipment, as it's one of the few greases approved for that use. Ask nicely.)
Lubriplate also makes SFL in heavier grades, which are more readily available in common cartridges. Finding the NLGI #1 is fairly easy, and I've had good luck with it, but really prefer the lighter grease - when I can get it! In either grade, this is such a superb product that it is worth searching out.
If you can't find it (and I wouldn't be surprised if you can't), Lubriplate also makes a similar product known as "SFO" grease. Also aluminum-based, it shares many of the same characteristics of the SFL grease, except for the extreme low temperature performance. (If you spend most of your time with a dog team in the Yukon, then it might be a problem. Just about anywhere else, it won't be.) The NLGI #0 weight comes in 14 oz. cartridges, and is far easier to find than the SFL #0. Check with bearing suppliers in your area; if they don't have it, they can probably get it fairly easily.
But what about......?
Everyone has their own little "secret". If it works, is there anything wrong with it? Let's find out...
Motor oils: Generally good boundary lubrication (particularly the Havoline formulations), but very poor corrosion resistance and poor resistance to open-air oxidation. In addition, their pour-point additives often contain benzene compounds, which aren't a good thing to have next to your skin on a regular basis! ATF is better on every count, even if it is a tad more expensive. (ATF is still 1/10 to 1/100th the cost of a specialty "gun oil"!)
Gear oils: Almost invariably too thick for the application. In addition, they contain tackifiers which gives them poor migration and lead to oxidization in open air, rendering them even more "sticky" - pretty much what you don't want! (Many folks use it on their slide rails because it's thicker and won't migrate easily; that's why we have grease, people!) If you really want a thicker oil with all the good characteristics we've covered, mix ATF and STP Oil Treatment in a 40/60 ratio. Far better than gear oil on every count.
WD-40: WD-40 was never meant to be a lubricant - it was designed as a moisture displacement agent. It's far too light for any load protection, has incredibly poor corrosion resistance, contains zero boundary lubricants, and rapidly oxidizes to form a sickly yellow varnish (hint: this is not good for delicate internal lockwork.) There are those who will defend this stuff vehemently, but then again you can still find people who think smokeless powder is a passing fad.
Automotive motor oil additives: Usually a boundary additive in some sort of light mineral oil carrier, they all lack corrosion protection and often oxidize rapidly; some have poor migration characteristics and rely on the oil to which they'll be added to provide those things. There are better and cheaper alternatives; save your money.
Silicone spray: Right up there with WD-40, but at least it'll shed water while your parts grind themselves into little shavings!
Graphite: (sprays, powders) Graphite is a crystalline product which is actually very slightly abrasive. It offers no appreciable benefit other than being dry; a lube with a good boundary lubricant package can be wiped dry to the touch and still provide better lubrication and protection than graphite.
Finally, note that the foregoing is a layman's understanding of lubrication technology. I don't pretend to be an expert, just a well-informed amateur hoping to disseminate some arcane knowledge. Use at your own risk!
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For all defending WD-40 as anything more than a water displacer, please, do not let the facts of lubrication physics vs. WD-40's formulation get in your way. Perhaps we can discuss if the Earth is really round next.
Just my 2 cents.Actually I think grease is better for the door hinge job. Another place where WD-40 is at the bottom rung of possible solutions. WD-40. The name says it all. Water Displacement. That's what it was designed to do. Any other use for it is accidental and it always among the worst possible choice, but sometimes it has to fill in because nothing else is at hand. Like duct tape and bailing wire it can be a versatile fill-in until the correct fix can be applied.