Do Steel Guns Absorb Oil?

[BarryLee]

I was in the LGS and a guy was packing up a new SA 1911. The guy behind the counter was going over a few issues and the guy asked him how to keep the gun from rusting. The employee told him to cover the outside of the gun very liberally with oil and let it sit over night and the oil would be absorbed into the pores of the steel.

OK, I have heard this idea that steel absorbs oil a few times and was just curious if this is really true. What impact does the steel being finished have on the ability to absorb oil? Does it differ between stainless and standard or forged and cast?

I guess my feeling always has been that this is not really true and that steel does not absorb oil. I just assumed that when left overnight the volatiles evaporate and it appears that the oil was absorbed. Can anyone say definitively if steel absorbs oil or not?

 

[Fishbed77]

Some finishes (parkerization and black oxide, I believe) are designed to absorb oil.

 

[Doyle]

Yes - to a certain extent. Steel (no matter how smoothly polished) has microscopic pits where oil will collect. I wouldn't call them pores as they don't go through the metal (i.e. oil placed on one side of the steel would never get to the other side). That is the reason you absolutely must re-oil whenever you use an oil stripper like brake cleaner.

Now, as to whether or not it will take on more oil from an overnight soak than it will from a rubdown is up for debate. In my small opinion, a rubdown puts enough oil on the metal to do the job.

 

[carguychris]

Steel (no matter how smoothly polished) has microscopic pits where oil will collect. I wouldn't call them pores as they don't go through the metal...

+1, and speaking of which...

Some finishes (parkerization and black oxide, I believe) are designed to absorb oil.

Again, "absorb" isn't necessarily the correct term; these finishes just have many more and deeper pits. Parkerized and oxide finishes supposedly don't possess any inherent anti-corrosion properties; their sole function is to hold more oil than a glossy finish.

Now, as to whether or not it will take on more oil from an overnight soak than it will from a rubdown is up for debate. In my small opinion, a rubdown puts enough oil on the metal to do the job.

IMHO the overnight soak falls into the "Dubious But Can't Hurt" category.

OTOH most of my guns get fired, cleaned, and re-oiled frequently enough that I'm not overly concerned with the need to soak a new one overnight.

 

[Clifford L. Hughes]

Barry Lee:

In terms of a sponge guns don't absorb oil. However, when a gun is wiped down with oil the pores fill even though they can't be seen. A light coat of oil is all that is necessary.

Semper Fi.
Gunnery sergeant
Clifford L. Hughes
USMC Retired

 

[Bill DeShivs]

Steel definitely does not absorb oil. The LGS guy is full of -it.

 

[Fleet]

Steel definitely does not absorb oil. The LGS guy is full of -it.

Absolutely true. Steel has what are called "asperities", no matter how finely polished. Even in a steel mirror, they still exist.
An easy way to visualize is think of how the surface of the earth looks. If you're far enough away, it's a perfectly smooth surface. Up close, lots of mountains, valleys etc. A polished steel surface is the same, but you may need a microscope to see it depending on the level of polish. The oil doesn't soak in, but it will settle in the low spots, and surface tension will allow some of the oil to be retained on the higher spots, but only for a time. Gravity still works, and the oil film on the highs will eventually run off.

 

[Mike Irwin]

"An easy way to visualize is think of how the surface of the earth looks."

It's very interesting to see a "smooth" surface like a highly polished ball bearing under extreme magnification, such as under an electron microscope.

It looks like the Himalayas.

 

[lyodbraun]

LOL yeah Steel will not absorb oil LOL.... Thats like saying this stuff actually works LOL .....

 

[Jim Watson]

Certainly there are surface irregularities at any given degree of polish, and they will hold some lubricant. That is what the engine turning or "jeweling" applied to decorate a bolt was originally for. And one gunsmith said he didn't polish working surfaces mirror bright, that a well rounded tool mark was a good lube holder.

But absorb into the "pores" of the steel?
No.
That smacks of the old theory that barrel corrosion was caused by "acid gases" seeping out of the pores of the steel after normal cleaning. Now we know it was the potassium chloride primer residue that oily nitro solvents could not dissolve.

I always say that I don't want a gun made out of material so porous as to absorb oil. Although there is one gunsmith who will put a porous bronze Oilite bushing in your revolver hammer.

 

[mete]

Powder metals will certainly absorb oil like the bearings .Otherwise it's just the oxide on the surface .That could be natural oxide , bluing and especially Parkerizing.

 

[mo84]

Its kinda like a cast iron pan the longer you lightly oil it the better it gets.

'

 

[Kreyzhorse]

In terms of a sponge guns don't absorb oil. However, when a gun is wiped down with oil the pores fill even though they can't be seen. A light coat of oil is all that is necessary.

+1.

There is no reason to leave excess oil on a gun to allow it to soak in.

 

[Doyle]

Its kinda like a cast iron pan the longer you lightly oil it the better it gets.

Actually, the cast iron is getting better from the layer of carbon building up (which does come from the oil that burns on ).

 

[tekarra]

Powder metallurgy is used in bearings as the density of the finished can be altered by the pressing force used to form the part. The green pressing is then sintered to fuse the metal particles creating a solid part with internal voids. The voids will fill with oil if so desired. However, firearms are not made using powder metallurgy principles. Let us leave MIM out of the discussion.

Likewise firearms are not made of cast irons so that analogy does not hold either. Cast iron frying pans are left rough so oil and grease can collect in pockets which is a surface condition. I do not think anyone would want a firearm with a surface as rough as a frying pan.

 

[mete]

You guys need education. Remington has made powder metal parts for guns and other things for at least 40 years ! They now have added MIM to their production ! I don't know of any gun parts that are used because they hold oil. In fact the Remington PM specialized in extra density parts very close to wrought metal.

Cast iron pans are treated with soy oil [the best type] and the oil is heated oxidizing and polymerizing the oil to form a 'plastic' coating.

 

[Jim Watson]

However, firearms are not made using powder metallurgy principles.

This would have been news to Colt in 1969 when they brought out the Mk III revolvers with sintered metal guts; likewise Dan Wessons of the 1970s.

 

[montelores]

The LGS fellow was correct, but he didn't give you the full story.

He was referring to "blued steel," although he might not have been aware of the details.

When steel is "blued,", it is, in effect, "rusting" (or "oxidizing") the metal.

When oil is applied to a "blued" steel, the oil prevents further oxidation.

The oxidized surface is not uniform, and the oil resides in the oxidized surface.

This same process does not apply, obviously, to unfinished stainless steel.

You can prove for yourself that "bluing" is "rust" by wiping an oiled rag over a new blued gun. The rag will have a slight brown tint to it. This is "rust."

Monty




Black oxide provides minimal protection against corrosion, unless also treated with a water-displacing oil to reduce wetting and galvanic action.

All blued parts still need to be properly oiled to prevent rust. Bluing, being a chemical conversion coating, is not as robust against wear and corrosion resistance as plated coatings, and is typically no thicker than 2.5 micrometres (0.0001 inches). For this reason, it is considered not to add any appreciable thickness to precisely-machined gun parts.


This is one of the reasons Rust and Fume bluing tend to be more rust resistant than any other method. The parts are then oiled and allowed to stand overnight. This process leaves a deep blue/black finish.

http://en.wikipedia.org/wiki/Bluing_(steel)

 

[kozak6]

This same process does not apply, obviously, to unfinished stainless steel.

Kind of. The chromium in stainless steel "rusts" in the presence of oxygen to form a passivating layer of chromium oxide(s?).

The pistol in question was probably parkerized. The phosphate coating formed by parkerizing is relatively porous and needs to hold oil to be effective.

There's even those who advocate baking parkerized parts in vasoline to maximize oil absorbtion.

 

[claymore1500]

Here is where I get the flame treatment, As to steel absorbing oil, No it does not, but, oil will migrate thru the metal.

Density and thickness will determine how long it takes and an overnight soak will not do it, but the reason that this type of oil can almost always feels oily, no mater how clean you keep it, is due to the oil working it's way thru the metal.

You can prove it, buy a new one, fill it about 2/3 full, spray it with brake cleaner and allow to dry, then set it some where, it may take anywhere from a couple of weeks to a year, but eventually it will be oily on the outside.