Listening for pin drops is a misnomer

When teaching beginners how to pick, I find that quickly they learn that they can hold the lock up to their ear and listen for pins dropping as they release tension on the wrench.  If you have lifted pins up at all, the springs will snap them back into position with a little ‘click’.  If you know how many pins is in the lock (which you should) they you can ‘see how close you were.’

This doesn’t work.

There are two common errors in beginning lockpicking.  The first is too much tension.  This is a problem because if you rotate the cylinder within the lock too much, every pin will feel like it is binding.  You will hold both pins against the shear no matter what, and you’ll get a very bad level of feedback of actually lifting over the shear line.

The second mistake is overlifting.  Few people know how little pressure is required to actually life the key pin, and it is common the just ram the whole pin stack all the way to the roof witho0ut stopping at the shear line – a problem complicated by providing too much tension.

Overlifted Pin

Those two problems combine for a false sense of what is happening inside the lock.  If you lift all of the key pins into the shear line – very easy on cheap locks – and then release tension, you’ll be able to hear all of the pins drop.  This causes the ‘oh, but I had it, ‘cause I could hear them drop’ problem.  The problem is that you didn’t have it, there is nothing wrong with the lock, you just overlifted.  It’s a common problem.

The best thing you can do is not listen at all in my opinion.  It’s like sniffing the cork when tasting wine – it’s not going to tell you anything.  The sommelier offers you the cork to you can make sure it isn’t dry or crumbling – NOW so you can sniff it.  Experienced pickers listen at a lock to see if they have something in particular, not just to see if they have any pins lifted.  I sometimes listen early on, to see if my feedback is lying to me.  I try and set one pin, and then see if it snaps back.  I don’t know if it is overlifted, or just jammed into position with too much tension.  But I do know if I made one pin stick.

So, don’t listen at the lock, at least when starting out.  Trust your fingers, and start with easy locks.

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Bill Sempf

Husband. Father. Pentester. Secure software composer. Brewer. Lockpicker. Ninja. Insurrectionist. Lumberjack. All words that have been used to describe me recently. I help people write more secure software.

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