I don't personally use it but I says on the can it can be used. Also whats a good way to clean your lower especially if you get debris in it? I've seen guys like Jerry Miculek use Lucas contact cleaner on lowers.

I use it at times. More as a cleaner than a lube tho.

Back in the mid 80s we got a memo from the FBI at the department saying that WD-40 could cause primers not to ignite if used on firearms.  Sgt says no WD-40.  Haven't used it since.



I have no idea if it actually caused problems with primers, but I did see the memo with my own eyes.

WD-40 can be used as a cleaner, but it's not a good lubricant and tends to gum up quickly.
If you use it, spray the parts thoroughly and let soak a while.  They wipe it off and apply an actual lubricant.

I don't think I'd use it in a trigger group because it will soak into the pins and pin holes and can't be wiped off.
That will gum up and cause problems.
If you want something better, Rem-Oil is a good cleaner and a fair lubricant, although it's fairly thin and tends to run off.
It will dissolve old lube and flush out debris, then soak into all areas and lubricate without gumming up.

Apparently the idea that something like WD-40 can infiltrate a primer and cause dead primers is not true.
The "Box O Truth" did a test where they put primed cases head up in blocks and put good drops of various penetrating fluids on the primers.
After some good soaking not one primer failed.  

Used it once a long time ago as lube/corrosion inhibitor. Guns rusted. Only time I've used it since it's when shotgun got rained on to chase water out.

As long as you can wipe off all the areas you apply it, it is passable. I would not let it get in primers or hard to clean gas systems. My Dads old BAR froze up from years of that stuff turning into a plasticy crud.

What about lucas contact cleaner?

18 yrs ago I put 50 rounds of black hills 9mm, and 50 rounds of corbon 165gr .40 cal in jars filled with WD-40.

I left them in it for months.

I drained them, rolled them in a towel to wipe them off, then went to the range.


Every single round fired. No squibs, no failures of any kind with the guns or ammo.

+1 WD-40 is good for cutting old grease and crud. It's not a very good lubricant though.

Rem-oil is just as good as a cleaner and rust inhibitor, but doesn't gum up like WD-40.  Neither is a good lubricant.

Best product to use after a boating accident: wd-40

Wd 40 is a good cleaner. Removes and prevents rust.
But after cleaning its bettervto remove it spraying gun oil. It can become kind of gum paste if not removed.