Friday, February 03, 2012

Somewhere in the last two weeks or so

Someone had a blog post about how W-40 killing primers.
That cops used to spray down CCW weapons so the bullets wouldn't work- if I remember right.

Anyway- I asked how WD-40 could kill a primer by being sprayed on a sealed bullet.
According to the Box-O-truth- the only way oil kills a primer is if the primer is open to the oil.


  1. This is true. That is why you do not use any petroleum based oil, or WD-40 as a case lube. This is also why you make sure your cases are completely dry before you prime them.

    it seems to me that spraying them with anything after the bullet is sealed is a very low probability of penetration and therefore a very low probability of preventing the bullet from working. Most bullets are not sealed or watertight, but rely on tight fitting components to seal out the weather. They do make a sealant though if that kind of thing keeps you awake at night.

  2. This was a blog post (that I can't remember where) that the PD would routinely WD-40 any CCW weapons bullets they came across to ruin the primer.

    1. Back in the late 1950s when I first started handloading primers were very sensitive to oil of almost any type. Over the next forty years or so the companies worked hard to overcome that. By the turn of this century primers were almost completely oil resistant. Still, WD40 and Kroil, among other oils, are designed to penetrate.

      I sprayed ammo with various oils back in the early 2000s to test this. Now spraying ammo in new cases, with nice tight primer pockets does almost nothing to live ammo. Ammo that had been loaded in old cases with loose primer pockets was a lot more sensitive. Even then it took a while for the oil to take effect. Heck I took primed cases and prayed the oil right down them and the primers still popped after a few days. It took a week to ten days, depending on brand, to kill a third of the primers.

      and the companies have been working on oil and waterproofing primers since then.

  3. Last week, I test-fired an alloy-frame S&W Airwieght revolver that had been in a sewage backup and left in it's rug in a steel box for over a year. There was a box of .38 special wadcutter ammo in the box with the gun.

    Fired it in a vise with a string for the first six rounds, as the cylinder had some corrosion. No problem. So, I ran a few dozen more rounds through it to use up the old ammo.

    These were Federal factory loads from the 1970s. I had five misfires out of maybe thirty rounds I tested. The brass cases were green with corrosion and had to be polished with Scotchbrite to fit into the cylinder.

    Not bad for ammo left sitting in sewage for days.

    Anyone thinking simply spraying something on ammo can kill it instantly is asking for problems. Magic doesn't work except in the movies.

  4. Remember, too, that the vast majority of LEOs are not shooters. As a matter of fact if an LEO takes the effort to really learn the art and science of the gun (s)he will be looked on as odd and slightly suspect. It's a far cry from in my younger days when an officer or a deputy was paid extra for being on the pistol team.

    So a helluva lot of misimformation is being passed on in locker rooms. And things that were correct back in, say, 1952 but haven't been true for decades, are still passed as gospel.

    When I hired on we still all used revolvers. Our practice ammo was handloaded in the county jail by trustees. I worked for three solid years to make the pistol team and, five years later it was cut. Before that the jailhouse ammo factory disappeared.