View Full Version : WD-40 in firearms?

El Chimango Pete
March 27, 1999, 04:55 PM
on another forum ("Cybershooters" from the UK) I found dire warnings against using WD-40 spray in cleaning/preserving guns - any comments? (personally i love the smell of Hoppes No. 9 in the morning... but WD is usually found just about anywhere - never heard of it being harmful until now)

March 27, 1999, 08:49 PM
One thing you don't ever want to do is get WD-40 on a good wood stock or pair of wood handgun grips. The finish will be gone or ruined for life.


"NJ...The First Communist State in the Union"

Rich Lucibella
March 27, 1999, 10:21 PM
WD40 is not only a *lubricant* but an effective *penetrant* (read the label). It is the penetrant properties that are damaging. While these work well in removing rust and corrosion, they can be *devastating* to well kept metal surfaces.

Also, as penetrant, a small quantity of WD on bullets can neutralize the primers. Test this by putting a few WD40 coated rounds in a zip lock bag for a week. You're bound to get one or two "sizzlers" at the end of that time.

March 28, 1999, 11:56 PM
im a gunsmith and wd-40 has made me more money than anything else. wd-40 will get gummy and even harden up after a period of time. heat and dirt speed up this process.
if your going to use it keep it on the outside. do not put any on the inside of the gun. use rem-oil or equivalent.

March 29, 1999, 01:56 AM
Here we go again. Sorry that I cannot quote the source but from a reply in a gun magazine publication from a few years past a company rep stated unequivocally that the use of WD40 will NOT harm gun metal in any way. He stated that the only exception was firing rounds thru a bore that was not first swabbed and cleaned of its carrier.

Because no matter how much care is excercised in keeping WD40 away from ammo primers, the possibility of neutralizing them is there. For that reason alone I do not use it on my business pieces. Hope this helps.


"To earn a million is easy, a real friend is not."

James K
March 29, 1999, 02:37 PM
WD-40 will gum up and will harm SOME wood finishes. In moist areas, WD-40 WILL MILDEW and hurt the finish. (Yes, I know guns should not be stored in moist areas, but my point is that the WD-40 itself is what mildews, not the gun finish.)

Also avoid using Hoppe's #9 on nickel plated guns. It will not harm the nickel, but nickel plating has a copper under plating and Hoppe's attacks copper (which is why it does a fine job of cleaning copper fouling out of bores). If it can get to the copper, like at the muzzle or through a scratch, chip, edge of sideplate, etc., it will cause peeling of the nickel.

Gun Scrubber does a good cleanup job, but removes ALL protection from the metal, so if you use it, restore the oil or whatever after use.

My vote goes to G96 Gun Treatment, which has never given me any problems and which cleans and protects.

P.S. W A R N I N G ------------

[This message has been edited by Jim Keenan (edited March 29, 1999).]

4V50 Gary
March 29, 1999, 03:54 PM
While I would rather use WD40 than nothing, if I had a decent gun oil or lubricant, I'd opt for that first.

Remember that lawsuit originating in Texas where this old feller, while seated in his pick up truck, shot himself in the foot when he jarred his rifle? Well, turns out that for years our unfortunate cohort had been spraying his gun down with WD40 and had never bothered to have it disassembled and cleaned. Like Bjordan740 says, it gums up and sure enough, the surface area between the sear and the safety became like a flat plane. This was the cause of the Remington discharging. Had the unplucky shooter bothered to take it to the gunsmith for regular inspection and cleaning, this could have been prevented.

It took two employees at the factory to separate the action from the stock - and this was after the gun was placed in the vise. Well, Remington lost even though it wasn't their fault. Sadly, the law firm and the negligent owner are both millons richer.

Please no WD40 unless there's absolutely nothing else.

Art Eatman
March 30, 1999, 12:55 AM
I'll use WD40, but mostly by first spraying it on a patch and *then* apply it to a gun. Back before we had the clean-burning gunpowders of today, I'd spray it directly into a Govt. model to flush out grunge. The issue of hardening and dirt buildup didn't apply, since I disassembled the pistol for thorough cleaning after the shooting session.

It is wonderful stuff if you've had your gun out in the rain. "WD" stands for "Water Dispersant" or something like that, and the 40 refers to the 40th formula tried by the inventor. It will make moisture bead up and run off metal--a lifesaver out at a huntcamp.

But for sure, keep WD40 or any other cleaner/lubricant away from scope lenses and away from ammunition. Any good oil will "creep" and find its way into all manner of "wrong" places.

If only folks took care of guns and cars the way pilot/owners take care of airplanes...

Walt Welch
March 30, 1999, 04:52 AM
WD-40 is good for only one thing. If you get adhesive on your knife blade from cutting packaging tape, the WD-40 will remove it nicely. As a lubricant, it is very poor. As noted above, it is also prone to gumming.

As far as primer inactivation goes, only a foolish person would apply WD-40 to the cartridge head of a loaded round. However, a gunsmith, Geoff Benze, has been doing a study for over a year with (loose) primers soaking in WD-40 and others soaking in water.

The WD-40 soaked primers worked perfectly well after one year's submersion, immediately after being removed from the liquid, and after air drying.

The water soaked primers wouldn't work when wet. After they were air dried, however, they worked perfectly.

Once again, I am NOT advocating putting WD-40 anywhere near your primers, but the problem may not be as bad as some people think.

There are much better products on the market now for rust prevention and lubrication. One of the best, and most convenient, is Sentry's Tuf-Cloth; this will protect a finish extremely well. The compound in the cloth bonds to the metal, and is completely non tacky in a few seconds. The cloth comes in a heavy plastic zip lock bag, and you just take it out, wipe down your gun, and return the cloth to its' bag.

Sentry also makes a bore protectant, which allegedly smooths the bbl. and minimizes or prevents leading. This is Smooth-Kote. Tuf-Glide, the active ingredient in Tuf-Cloth, is also available in an applicator bottle, and is a terrific lubricant, also 'sticking' to the surface of the firearm. One more product is BP-2000, which is a powder you apply to critical areas like trigger contact surfaces and hammer-sear interfaces.

You can get an armorer's kit, which contains all of the above products for about $30 from Discount Knives :


Just for the record, I have nothing to do with Discount Knives or Sentry Products, other than being a satisfied customer.
I owe the pristine bluing of my 1957 GC to a Tuf-Cloth. I was shooting with a number of people in AZ last year, and discovered to my dismay that no one had any cleaning equipment to loan me; they were all shooting Glocks. Fortunately, one had a sample size Tuf-Cloth, and that saved the bluing on my GC. Hope this helps, Walt

March 30, 1999, 10:57 AM
WD40 sure takes black shoe polish off the kitchen counter. (Next time I polish shoes outside...)

A local mechanic says WD40 is great on auto and boat spark plug leads - apparently for the water dispersant effect. He's also a shooter and violently opposes WD40 on firearms saying WD40 creates gunky buildup (as explained above).

Tom B
April 2, 1999, 06:47 AM
Let me quote from the industrial high voltage course that I took and now teach within my company. This comes from The Multiamp Institute in Dallas TX. "WD40 is not a petroleum based lubricant. It's lubricating values only last for about 20 minutes." As far as a rust preventative I do not know.

March 24, 2010, 06:17 PM
I've been using WD-40 on all of my guns for the past 30 years with no adverse effects at all. It's a dry lubricant and penetrates to get out all the dirt that was attracted to the Rem oil I used after cleaning the gun with WD-40. It hasn't ruined any of the metal parts or gummed them up. The correct way to clean a gun is to remove all metal from the wooden stock so it's not an issue on the wood finish anyway. Use your head! Do you soak your ammunition in Rem oil? Why would you soak them in WD-40 as previously mentioned in this thread. The bore and breach of the gun is supposed to be wiped free of heavy oil residue BEFORE firing a chunk of lead down the barrel in the first place. If you don't, you're courting disaster. Bottom line from an experience firearm handler and abuser, WD-40 is great stuff for cleaning all of the metal parts, period.

March 24, 2010, 06:55 PM

This one was finished 11 years ago. Egads man!

March 24, 2010, 06:56 PM
Remember folks, WD-40....Water Displacement-40th Formula. Do I use WD40 on my guns? Sure...When they have had over exposure to water. If it gets totally rained on while hiking, gets dropped into a nasty mud puddle, or godforbid gets dropped into a stream/lake/river/whatever, I'll use the WD to displace the water from the surface of the metal and cracks/crevis. But will always follow up with my normal cleaning routine.... 1) Hoppes, 2) WD if needed, 3) Hoppes again to clean the WD out, 4) TetraLube.

I dont think WD40 will actually harm any of the metals, but I do know that it provides very poor lubrication for a firearm. Door hinges...OK, but not a firearm.

Edit: Wow, didnt even notice the date on the OP. You're right Yankee, can we get Mods to lock this one?

March 24, 2010, 07:29 PM
Ill use it to free stubborn or frozen screws and nuts, but for protection and lubrication nothing beats CLP Breakfree.

March 24, 2010, 07:31 PM

This one was finished 11 years ago. Egads man!

+1 and a WD40 thread at that there are plenty of more recent ones still open.:D

March 24, 2010, 07:49 PM
WD-40 evaporates. I used to use it to lube the hinges on my car doors. Had to reapply every 6 months or so.

Sprayed some Breakfree CLP on the hinges 2 years ago, still nice n silent:D

Shane Tuttle
March 24, 2010, 09:43 PM
This one was finished 11 years ago. Egads man!

Yep. And others just love to pile it on instead of letting it die. An OLD, WD40 thread....