Using Motor Oil for Gun Lube

If you're hunting for a better lube, you have a defective gun. I just use literally whatever, and everything runs fine
That has been my experience as well. However...

Some types of lubes work better as evidenced by increased cleanliness and cycling reliability, especially when shooting lots of rounds between cleaning (at shooting range). Mobil One (and probably all detergent motor oils) excel at this. My guns stayed cleaner longer and cycled more reliably using motor oil.

Gun cleaning after a trip to range was also much easier when gun lubricated with motor oil. A quick wipe with a cotton rag or cleaning patch easily removes used oil and burnt powder residue. After I started using motor oil, I no longer needed to scrub with a brush and solvent. When I used gun oil, gun cleaning was more work (requiring scrubbing with brush and solvent).

The detergent in motor oil is very effective at preventing buildup of burnt gun powder. That makes sense because engine internal combustion is a dirty, high heat situation. Motor oils are over engineered for that, which means they're extreme overkill good for guns. Also, motor oil is free (for guns).

Motor oil is free for your guns (if you use whatever you put in your car or truck) because a frequent shooter will likely use less than 1/8 a quart per year.
 
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I've been mixing Mobil1 5w30 with Mobil1 Syn grease for a while now. It works well.
I'm sure that does work well.

However, if you use 15w40 (like I do) or 20w50 then it'd already be thick enough that you wouldn't need to mix it with grease. i.e. - using 15wXX or 20wXX is more convenient than what you're doing. Effectiveness would be similar.
 
I've been mixing Mobil1 5w30 with Mobil1 Syn grease for a while now. It works well.
While you can of course use them separately - mixing the M1 oil + M1 grease together to form a honey like pour thickness makes for a great semi - auto pistol and AR lube .
 
I wonder how Valvoline Restore and Protect 10w40 will go at protecting against fouling? :ROFLMAO:
I’ll save a bit when I finally buy some.
 
I have used motor oil for years, and still do. (Mobil 1 in whatever viscosity I have around). It works fine. I also like to try the new lubes as well, because I like to mess around that way. After all, this is BITOG. I probably have at least a couple dozen different "gun lubes" lying around.

But it's like Astro said, guns are not that difficult of machinery to keep lubricated. A few drops of whatever here and there, and you're good to go.

Learning where, along with how much, is more important than the type of oil you use.
 
My brother used to shoot competition. Most of the guys he shot with used a mixture of STP and Marvel Mystery Oil. On their 45's at least.
They were mixing a thick lube with a thin, high detergent lube to arrive at a medium viscosity lube with detergent in it. Motor oil is a medium viscosity lube with detergent in it.

Either STP/Marvel or a grease/Marvel mix would work well. Motor oil also works well.

However, buying 2 things and mixing them is not economical or convenient.

Motor oil is free because you already have it for your car and 1/16 of a quart is enough for 1-2 years of shooting every weekend. Motor oil is convenient because there's nothing to mix.
 
You lost me at “slipperier”.

Look, guns aren’t that particular about the oil.

Also, it takes 5 drops to lubricate a Glock - so, that means that an ounce does about 100 guns.

So, compared with the 10,000+ rounds it takes to require that kind of lubrication, who cares about the cost of gun oil?

I would rather have a dedicated product for guns, personally, but your gun doesn’t care.

Nor does it know that motor oil is “slipperier”…if your gun doesn’t cycle reliably, you have a gun problem, not an oil problem.
I would have continued using gun oil if it was better. I tried motor oil and it was clearly better. So from then on I used motor oil. Being free was a bonus.
 
I wonder how Valvoline Restore and Protect 10w40 will go at protecting against fouling? :ROFLMAO:
I’ll save a bit when I finally buy some.
I like Mobil One 15w40. I never tried 20w50 but I suspect it'd be good. Probably a straight 15W or 20W would be good too.

10W40 might be a bit thinner than I prefer, but it's thicker than Remoil. So 10w40 would probably work well enough. Likely better than Remoil or any thin gun oil.

The South Americans use whatever motor oil they use in their cars and it works well for them. I don't think they're picky about brand or viscosity. The main thing is to use a detergent oil because it helps prevent buildup of combustion deposits. I mean it helps prevent buildup of burnt powder.

These days all motor oils are detergent oils. So any motor oil should work. A higher detergent oil might keep gun cleaner than a lower detergent oil, but any motor oils will be better than the official gun oils and dry lubes I tried.

At least that's been my experience.
 
Motor oil is probably better than most gun oils on the market, and there aren't many guns that see enough rounds to actually wear out.

The detergent in motor is designed for a very small amount gunk. Guns generate orders of magnitude more debris per unit of volume than engines do. I don't think detergents will do much of anything in guns. Having a higher solvency base oil to dissolve the junk as it's made would be good. Engine base oils are the opposite of this.

Imho, the "ideal" firearm lube should have EP additives to fight against the sliding/boundary conditions not seen in engines.
 
They were mixing a thick lube with a thin, high detergent lube to arrive at a medium viscosity lube with detergent in it. Motor oil is a medium viscosity lube with detergent in it.

Either STP/Marvel or a grease/Marvel mix would work well. Motor oil also works well.

However, buying 2 things and mixing them is not economical or convenient.

Motor oil is free because you already have it for your car and 1/16 of a quart is enough for 1-2 years of shooting every weekend. Motor oil is convenient because there's nothing to mix.
Yes, but STP is sticky, and would stay longer. Don't ask me about the tendency to hold dirt.
 
It’s all personal preference. Guns don’t care too much what kind of oil, just that they are oiled. I prefer gun oils simply because of easier application and less smell. People hate on Rem Oil, but it’s great stuff, especially in extreme cold.
 
1) The right oil for the right application.

2) A gun is not an automobile engine. As far as I know.

3) Auto mechanics wear gloves because fluids like motor oil are toxic.

4) A lot of American gun people can't wait to come up with a way to "save money." Here's an idea: Don't buy a gun.
 
Home brew recommendations from a gunsmith.
He actually instructs AR15 technicians/builders for many of the largest AR15 manufacturers in the USA.
If you are a fan of the AR15, you probably already follow him.

 
Yes, but STP is sticky, and would stay longer. Don't ask me about the tendency to hold dirt.
I like 15W40 motor oil viscosity (the 15 number) because it's thick enough to stay put (even after shooting 100+ pistol rounds) until I'm ready to clean the gun. Then when I clean the gun, it wipes off easily and burnt powder residue easily wipes off with it. No solvent and no scrubbing required, except for Hoppys and a cleaning snake pulled through the barrel a few times. Cleanup is easy.
 
I have used motor oil on my AR15s as they get to run quite hot ona Carfbine Course.
Handguns I stick with tradtional gunoils, that are thinner and smell nicer such as Remoil

There are a lot of “better” products out there than Remoil. It’s one of the weaker products available.
 
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