"What oil/grease should I use on my gun?" is one of the classic
Let's start an argument* questions: And the answer is "It depends on the job at hand."
Now that I've complicated things from the start, consider that you've got two different qualities to consider: lubrication and corrosion protection.
- Lubrication is 'makes the working parts work as smoothly as possible.'
- Corrosion protection is 'prevents rust'.
In a way, lubrication is the easier job; it's inside where the moving parts are, somewhat protected from the elements. Corrosion protection has to be on the outside as well, preferably without getting all over everything,
and it has to resist falling or rubbing off while the piece is carried around.
Lubrication
The best explanation of the types of lubrication is
this article from Grant Cunningham, which I strongly recommend reading, and from which I'll quote:
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.
That said,
any lubricant is better than none. If all you've got is motor oil, use it. Bearing grease is too thick for a lot of gun uses, but it does work. Automatic transmission fluid (ATF for short) works, in fact I've been told it's the Army's go-to if standard CLP is not available.
There are, however, better lubes for different jobs. Something that provides outstanding corrosion protection might not be as good a lube as a dedicated lubricant, and some lubes are better for different jobs. The general rule I've heard is "Grease on sliding parts, oil on rotating parts". That means:
- Grease for things like frame and slide rails on pistols.
- Oil for things like hammer and trigger pivot pins, and link pins on barrels.
Lots of overlap there.
The thing about oil is that, being thinner, it will work its way into places that grease won't. Those pivot pins, for example: if you take things completely apart you can put grease anywhere, but if you just want to lubricate without complete disassembly, oil can be dropped onto where the hammer and pin meet. Work the parts a few times and the oil will work its way between the parts, and in places like that, it'll stay in place pretty well.
The advantage of grease in some places is it tends to stay in place. Pistol frame and slide rails, for example: most of the time a carried pistol is in a fairly vertical position, which has been known to cause some oils to slowly work their way downward, which could cause most of the rails to wind up with little-to-no lube remaining. Unless it's really hot (which causes it to get really thin), grease won't do that.
And don't forget weather! If you're out in seriously cold conditions, you need something that won't thicken enough to slow down the parts as they move. Similarly, a thick oil or grease that's wonderful on a centerfire might not be what you want on a .22LR.
Simply put:
- Use something that has the stuff needed for both hydro and barrier lubrication.
- Pick what'll generally stay where it should,
- and won't get too thick in really cold weather.
I know, I know. "You call all that simple?"
Which one?
There are more gun oils and greases out there than I care to count, let alone try, every one of them claiming to be the finest thing since Daniel Boone had to render some bear fat down for his flintlock. And generally speaking, they all work -- some better than others, but they all work.
Some have additives to make them a cleaner as well, some have protectant qualities (which is where you get CLP, Cleaner/Lubricant/Protectant). The general rule is "Something that does it all doesn't do all of them as well", but it also means you can use a single stuff for everything. Unless you need a better protectant, or something is
really fouled and needs better cleaning stuff, an all-in-one is really handy.
Corrosion Protection
As mentioned earlier, most anything takes care of that inside the mechanism. Something that stays in place on the outside and keeps the wet off is a bit more tricky. This is also why so many firearms makers started going to some type of metal finish that deals with corrision: aluminum AR receivers and handguards and such are anodized to protect them; steel barrels are parkerized or have some other type of coating.
For protecting plain steel parts, you have multiple options:
- Paste wax. I've known people who swear by it. Clean all previous oil or whatever off, apply a thin coat, let it dry completely, repeat a time or two. It makes a thin, clear, fairly hard coating that repels moisture quite well. High-tech it's not, but it works.
- Eezox is my favorite. It's actually a CLP, but I use it primarily as a protectant. It goes on wet, the carrier evaporates, and a thin coat is left behind. It does clean, it does lube, but I love it for keeping rust away. Put it on properly and it'll last quite a while.
- Parkerizing is a zinc- or manganese-oxide coating that's bonded to the surface of the steel. While it provides a little protection on its own, what it really does is provide lots of places for oil or grease to hide and be very hard to get rubbed off. There is a very good piece on the subject here.
My "I've tried it" List
Over time I've tried a bunch of different stuff, sometimes because I needed something and it was cheap, sometimes just because I like to try stuff out. So here are some of the things I've tried and liked:
Eezox
It works pretty well as a CLP, but as noted above I primarily use it as a protectant.
Lubriplate SFL-0 Grease
Straight lubricant. I first heard of this stuff in Cunningham's post and dug around; I could find the SFL-1 on Amazon, but could only get the -0 directly from Lubriplate. These days you can get it at
Midway.
I've used it in revolvers, semi-auto pistols, and rifles of various kinds. It stays where you put it, lubes very well, lasts well, and doesn't stink. And that 14oz. can will last the average shooter for years. Probably many years.
Slipstream
Straight lubricant. I've tried both the oil and the grease; both are quite slippery, and I've had zero problems from them. I will warn you, though, that the lubricant in the stuff is
black, and if you get it on clothes, well, there will be a stain. Forever.
Joe’s Red Army Tier-One Operator Lube
CLP. This is a mix-it-yourself stuff; the base recipe makes about a gallon, but you can scale it down for making smaller batches. It seems to work quite well as a cleaner, is suitably slippery as a lube, and internally takes care of corrosion, but isn't something you'd want to wipe all over the exterior (or at least
I wouldn't). The nice thing about using it for cleaning is that it's inexpensive enough that you can use a lot of it on patches or swabs and not worry how much it cost.
Tetra Gun Grease
Straight lubricant. Pretty good stuff, but personally I prefer the Lubriplate. I can't prove it, but I think the Lubriplate spreads onto the parts better as they work, and it's a LOT less expensive.
Break-Free
CLP. It's been around a long time. It works.
Corrosion-X
Lube and protectant. It's an oil, seems to stay in place pretty well, and lubricates quite well. On the exterior it has the standard oil problem of 'rubs off with use'.
Ballistol
This is odd stuff; it was developed in Germany in the early 1900's, and it's still around, which ought to tell you something. It can also be used on wood and leather (which you'd never use this other stuff on), and works quite well as a cleaner. Where this stuff really shines for me is cleaning after corrosive-primed ammunition or black powder: mix it with water (proportions on the can) and it dissolves the trouble-making salts so they wipe away. It's the easiest, and least-stinky, method of cleaning both of these I've ever tried.
Mr. C's Super Sekrit Gun Oil
Straight lubricant. Mr. C sent me a bottle to try several years ago; it's good stuff, passed my "1911 .22 conversion test" with flying colors.
Microlon Gun Juice
Primarily lubricant, but also works as a cleaner. Interesting stuff.. it's a pretty permanent dry coating. I'll let the website instructions cover the the specifics of how to put it on, but it's basically "clean and degrease, heat, coat, let dry, repeat a few times." My son used it on his rifle and a M240 in Iraq and loved it; not only did it slick things up nicely, but when everyone else was cleaning the sludge that the dust and oil produced from their weapons, he could break his down, wipe them off, reassemble, and was done. There's lots of arguments about the stuff, ranging from "It's wonderful!" to "Don't believe it, it's crap!" Read and decide for yourself. I will say that for some purposes it does work, and well.
These are just the ones that I've tried and can actually remember; there are others that go in the category of "Worked, but not better than anything else."
Just remember this basic truth: almost ANY lube is better than none (and WD-40 counts as 'none', no matter what anyone says).
*other all-time favorites being Glock vs. 1911, Mary Ann or Ginger, and "What's the best oil to use in my bike?"