View Full Version : Bob Marvel's Custom Gun Oil

Harwood Loomis
28th July 2010, 22:51
Bob Marvel’s Custom Oil

Slick Stuff for Slicking up your Shootin’ Irons
Reviewed by Frank Ettin, Steve Clark, and Harwood Loomis for M1911.ORG


Awhile ago the M1911 Pistols Organization received samples of a lubricant intended specifically for firearms, Bob Marvel’s Custom Oil. The samples were given to three of our gun test contributing editors: Frank Ettin, Steve Clark, and Harwood Loomis. This report is a compilation of their findings after working with Bob Marvel’s Custom Oil for a somewhat extended period.

One point all three testers agreed on is that, given that the name on the bottle is “Marvel,” the oil should probably be called “Marvel Mystery Oil.” However, that name already belongs to another product, in the automotive market. Why do we say this product is a mystery? Well … because it works, and we don’t know why. The initial impression of all three testers was that the stuff has a viscosity pretty close to that of tap water on a hot day. Harwood, especially, was reluctant to even try it on a gun. But … anything to further the cause of scientific inquiry, so off we went. And, surprisingly, we found that Bob Marvel’s Custom Oil does work, not only as a cleaner (which is not a surprise for a product with such low viscosity) but also as a lubricant.


I finally had a chance to try out Bob Marvel's Custom Oil. Here's what happened.

I decided to try it out with my Ed Brown Kobra Carry. It was pretty dirty, not having been cleaned in several trips to the range, so I decided to start out by cleaning it with Marvel's Oil. Since the gun is stainless steel, it was pretty clear how well the Oil was working for cleaning. And it worked quite well. Almost all of the built-up grime wiped off easily using clean patches wet with the Oil, and a brush was needed in only a few spots like the feed ramp, the abutment in front of the feed ramp and the corners of the breech face.

The gun was then ready for lubrication and re-assembly. I have to admit to being somewhat skeptical because of the very low viscosity of the Oil. It's very light and seems watery. I prefer using grease on the top of the disconnector and the barrel feet, so I went ahead and lubed those spots with TW-25B lithium grease. But I used the Oil on the rails, barrel lugs, barrel hood, barrel and link. Racking the slide, everything felt slick. And then I was off to the range.

I shot about 150 rounds with the gun. I was clearing out some JHPs (about 28 rounds of El Dorado Starfires and 28 rounds of Federal Hydra-Shoks) that had been loaded in some magazines for about a year. And since I had recently come upon a small supply of Gold Dots, I tried the Ed Brown with 40 rounds of those. And I shot another 50 rounds of PMC 230 grain FMJs.

Everything worked just fine. No malfunctions and the gun generally ran like a champ. I was shooting about as fast as I could get away with there. Since the instructor group I'm with teaches Basic Handgun at that range, and they know me, they cut me a little slack.

I departed from my usual practice of letting a dirty gun properly age in the safe for a bit, and broke down and cleaned the Ed Brown as soon as I got home (the things I do for M1911.ORG). The gun was dirtier than I would have expected, but PMC ammunition is often pretty dirty.

I started by wiping down everything with clean, dry patches. The gun came remarkably clean very easily. Following up with some patches moistened with the Oil, a little more crud came off, and the gun was left clean.

The primary reason I cleaned the gun immediately is that I wanted to see if I could tell anything about how the Oil held up to the heat and friction of shooting. And, sure enough, there appeared to be a film of lubricant still on the rails when I took off the slide.

I remain somewhat skeptical of the low viscosity. How would Bob Marvel's Oil hold up if used on a carry gun? Is there going to be any lubrication left at the end of a week of sitting in the holster? When I put the Ed Brown back together, I again lubricated it with the Oil, and I'll see what it looks like after spending some time in the safe.

Of course, this hasn't been any kind of a scientific test. I don't even know how I'd try to do a meaningful test of a lubricant using stuff I'd find around the house. Bob Marvel's Custom Oil certainly seem to do a good job as a cleaner. And it also seems to have performed satisfactorily as a lubricant, but it also seems awfully thin.


I have used Bob Marvel’s Custom Oil since receiving the bottle in January of 2010. During the ensuing months, I have lubricated all four of my Colt 1911s, a Smith & Wesson Model 686-6 Plus .357 Magnum revolver, and a Glock Model 32 in .357 Sig. In addition, I have used Bob Marvel’s Custom Oil to lubricate two test pistols, an Iver Johnson Trojan and a Volkmann Custom Combat Custom. Here are my impressions, based on that usage.

I initially thought the oil had a rather unpleasant odor. After repeated use, I find the fragrance to be much less disagreeable than Hoppe’s #9, or Break-Free CLP.

The “turn-to-open, turn-to-close” applicator on the top of the bottle is nice for applying oil to the outside surface of a pistol, but less-than-ideal for application to small areas, like the frame rails and slide rails. For those areas, I use a cotton swab soaked in the oil. (I prefer needle applicators, like those found on some competing products.)


Clean-up of a pistol after an extended range session seems to be much easier than with other surface oils I have used. That statement means that the carbon deposits wipe off quickly from rails, barrel and slide lug areas, and the disconnect area and hammer on the frame. I still prefer Hoppe’s #9 for the inside of the barrel, feed ramp, and vertical impact surfaces.

Rubbing down the external surfaces of pistols with a rag containing Bob Marvel’s Custom Oil instantly removes fingerprints or minor carbon fouling. I have not detected any degradation of the surface oil, when applied to a firearm which is stored. The oil seems to “cling” to those parts which have been lubricated. While I haven’t shot any of the pistols mentioned for over 500 rounds between cleanings, the guns have appeared to remain adequately lubricated up to that semi-high round count.

Overall, Bob Marvel’s Custom Oil lives up to the claims printed on each bottle. I would personally prefer the option of a needle applicator. As to the question of whether I would buy this product instead of the lubricants I use now, I didn’t see anything to make me change what has worked for me for years.



Like my colleagues, I was initially quite dismayed at just how “watery” this oil seems. My long-time standby has been 15W50 synthetic motor oil with finely-ground molybdenum powder mixed into it. Bob Marvel’s Custom Oil is radically different from that. It apparently isn’t relying on viscosity to do its lubricating, so there must be something else about it that allows it to maintain film strength under heat and pressure. What is it that accomplishes that? I guess that’s what falls under the category of “proprietary formulation.” In other words, we don’t know and the manufacturer isn’t talking.

However, Bob Marvel’s credentials are both noteworthy and impeccable, so I set aside my initial hesitation because I decided if this product is good enough for Bob Marvel to put his name on it, it must have something going for it.

My approach to using Bob Marvel’s Custom Oil was to dribble the oil onto the end of a cotton swab and use the swab to apply a light coating of the oil to those surfaces where I wanted it. This worked especially well on the slide rails, distributing the thin oil uniformly without any drips or runs. Once the oil was applied and the pistol reassembled (I tried it on my Colt carry weapon), everything slide together cleanly and the slide felt exceptionally smooth when cycled manually. Although I expected the oil to thin out and evaporate or run off when the pistol heated up in firing, that did not seem to happen.

I also had occasion to demonstrate that this product is very good at eradicating emerging rust. While tinkering one evening in my basement “workshop,” I was horrified to peek inside the magazine well of my Colt M1991A1 Compact carry pistol and see a light coating of reddish-brown rust! We have been enduring record high temperatures coupled with very high humidity in my corner of the globe recently, so this shouldn’t have been a surprise … except that I’m generally pretty conscientious about keeping my firearms protected against the humidity, especially the one I carry.

As I was mentally berating myself for allowing things to get out of hand, my eye spotted the bottle of Bob Marvel’s Custom Oil sitting on the bench. “Why not?” I thought. I picked up the bottle, wetted the end of a cotton swab with the oil, and scrubbed away at the inside surfaces of the magazine well. A few seconds later there wasn’t a trace of rust remaining, and the oil appeared to have moderately impregnated the surface of the metal with what I hope will be a protective film. It has been almost a week, the pistol has been exposed to the same high heat and humidity, and there’s no sign of rust returning, so I think it’s working. While I was at it, I also removed the grip panels and wiped down the flats beneath in order to alleviate the tendency for moisture to collect between the grips and the frame, promoting hidden rust and pitting.


According to Marvel's own web site, Bob Marvel's Custom Oil offer the following qualities:

Excellent treatment that lubricates, penetrates, cleans, & preserves metals
Proven performance for semi/full automatic guns, black powder barrels & suppressors
Better than graphite, PTFE or synthetics
Reduces friction & carbon build-up
Provides protective coating
No build-up or tackiness
Protects against corrosion
Repels moisture
Effective in high & low temperatures
Safe to use on polymer

Our trials on 1911s confirmed these claims. Whatever makes up the chemical composition of this product, it appears to be well-suited for use on firearms and to live up to its claims.

You may discuss this article here (http://forum.m1911.org/showthread.php?p=799300#post799300)


Bob Marvel Custom Guns
Crete, NE

Packaging: 4-ounce plastic applicator bottle

MSRP: $8.50 / bottle

Web Site: http://bobmarvelcustomguns.com/bob-marvels-custom-oil.html