Bump Keys for Dummies

Relationship of key to pins in ordinary lock

Sometimes our staffers come across freelancer posts about topics with which they're unfamiliar, but are interesting enough that they decide to do a little research of their own. No one here, for instance, knows anything about locksmithing or, for that matter, burglary. On the other hand, our staffer suspected that eHowian freelancer Cecelia Owens knew even less about the topic of picking locks; especially after checking out the references she included in her HomeSteady.com post on "How to Open a Locked Door Using a Bump Key."

One of her two references is for how to use a "bumpkey hammer," and the other is a list of videos on how to pick locks; neither actually has the instructions Owens appears to have copied (sort of). So, we looked for our own reference, and by simply checking out wikipedia we learned the mechanics of bumping. Basically, the pins in a lock are all little spring-loaded pistons, and the key that matches the lock engages those pistons and pushes all of them into the position that allows the key to turn. In bumping, according to the article, all the pistons are "shocked" into the release position for just a moment, so the key must be turned while a bump key is being struck:

"...if a light rotational force is continuously applied to the key during the slight impact, the cylinder will turn during the short separation time of the key and driver pins..." That's not, however, what Owens says. According to Cecelia, the steps for using a bump key are, "Put the entire bump key into the door's lock..." "Strike the top of the bump key with the hammer or mallet three to five times..." "Turn the key counter-clockwise to unlock the door..."

Strange: if you follow those instructions, we're pretty certain the bump key isn't going to work because – unlike the actual step which requires that the key be turned "during the slight impact" – Cecelia's steps indicate that turning takes place after you've whacked the key with a hammer a few times. Oh, yeah, and our best reference to the technique says to pull the key back a tiny bit after it's been inserted. Owens also missed that little detail.
Oops: another woefully unqualified freelancer whose journalism degree apparently didn't teach her how to reword primary sources. In other words, another Dumbass of the Day.

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