Why is WD40 bad for your guns? Or is it?

I have seen several posts state that. Please explain.

 

It's not a lubricant, it wil separate and leave a gummy residue that will effect a mechanism like triggers etc. I have cleaned it out of the inside of several revolvers , rifles bolts and triggers. Spray it on shovels, it might keep them from rusting....Birchwood Casey makes "barricade " that is a moisture displacement that leaves no residue and is great to wipe down firearms (spray it on a cloth ) "Break Free" is a great lubricant, tested and proven....

 

Never discussed the science behind it, but a qualified gunsmith explained to me that the residual effects of it actually draws moisture. That was good enough for me.

 

WD40 was never made to be a proper lube. Break Free, Barricade, even a little Rem Oil are all way better choices.

 

As Ron said above it will turn gummy in trigger mechanisms but I'll take it one step further.... WD40 is a rust inhibitor and blueing is a form of rust.

You can test this for yourself:
First, take a small container like a spray paint cap and spray a 1/4" of WD40 in it. Set it aside and look at it 3 weeks later. It will look like syrup or varnish.

Next, take a clean white paper towel and spray WD 40 on it. Then wipe down the barrel of a blued gun that you know is clean. The paper towel will get rust colored marks on it. Repeated use over time will remove blueing...

Just my 2 cents worth.

 

Used it in my implement dealership for years on wet sparkplug. It does draw moisture Great for wires not guns.

 

the WD stands for water displacement it is not a lubricant. Roger C.

 

Years ago I was helping my friend Mike Crevar, a gunsmith of 50 years, and there was an old S & W .38 in the back of one of the safes.
It looked like it was covered in shellac. I asked what was up with that. He said he bought it, and about ten other pieces off of the guy’s widow. He knew the guy from our club and the guy had sprayed the thing with WD and forgot about it for YEARS
Mike kept it like that to show people why you don’t use that stuff to protect a gun.
You couldn’t move the latch to swing out the cylinder. Everything felt like it was welded together
He always joked if you wanted to make your own all you needed was some kerosene and a few drops of your wife’s perfume

 

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.