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I was reading about lock "bumping" where burglars buy 'bump' keys and can open locks very quickly. I was also reading that some locks are bump proof (double chamber perhaps?). My question is: how can I tell, by looking at the locks currently on my door, if they are bump proof or not?

I don't see any brand or manufacturer name on the locks but they were replaced 3 months ago when we bought the house.

If you are not familiar with bump keys or locks take a look at this video: http://www.youtube.com/watch?v=hr23tpWX8lM

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Sounds like security theatre to me. Have you heard of window "bumping?" A brick is an excellent tool for that. – Matt Ball Mar 24 '11 at 16:44
@Matt - "Security theatre"? With your logic why have locks at all? Bump proof locks are a deterrent, like any security measure, meant to buy you time. consumerreports.org/cro/home-garden/home-improvement/… – themerlinproject Mar 24 '11 at 19:58
I'm saying that it only provides the illusion of security. The illusion is sometimes enough of a deterrent.. Think of it this way: it's silly to worry about having a fireproof, drill-proof, bombproof, apocalypse-proof vault door that's right next to a window into the vault. And if you're really concerned about your locks, use a keypad, or retina scanner, or... – Matt Ball Mar 24 '11 at 20:03
Make it look less exciting to rob your house than the neighbor's... – Alex Feinman Aug 17 '11 at 20:32
Brick through the glass is the brute force method, scoring tool and duct-tape can be pretty noiseless. – Fiasco Labs Jan 14 '15 at 6:52
up vote 15 down vote accepted

I ordered a set of bump-keys and tried my doors. It was $15 (with shipping).

What's particularly interesting (at least to me) is that the method of 'bumping' open a lock has been around since the 1930s. It just wasn't well known by the general population until it was picked up by some TV shows/News stations in the 2000s.

Anyway - read the countermeasures section here: http://en.wikipedia.org/wiki/Lock_bumping

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I guess that is one way - ordering the bump keys and trying it. But my question is more of "can I tell by looking at my new locks if they are bump proof?" – themerlinproject Mar 24 '11 at 5:31
If it's a traditional lock that isn't advertised as bump proof; it isn't. If it is advertised as bump proof, it probably can still be bumped with additional hardware. It's like a 'pick-proof' traditional lock....the nature of how it works means it can be 'picked'. – Jimmy Mar 24 '11 at 14:02
Thanks, sounds like trying it with bump keys is really the only way to know for sure but it also sounds like any traditional lock is susceptible so I guess that is my answer. – themerlinproject Mar 24 '11 at 19:55
ordered some bump keys ($20 with shipping for me). Took all of 2 minutes - scary. – themerlinproject Mar 24 '11 at 20:10
@themerlinproject, for $2 and 20 minutes you could have just made one. :) BTW just because you cannot bump a lock doesn't mean it cant be done, it may just be your inexperience, or improper bumping method. – Unkwntech Apr 6 '11 at 5:58

If your lock is a just a simple pin tumbler then its vulnerable to bumping.

enter image description here

There are some pin tumbler locks that say they protect against bumping, but in practice it might be a little more difficult, but still very vulnerable. In fact the only deadbolt lock that I know of that isn't vulnerable to bumping, rakeing or other simple attacks. Is the Shalge Primus or another Hybrid key type. The pin tumbler on the primus is 100% vulnerable to bumping, however, the "side-bit milling" isn't vulnerable. Defense in depth security in layers.

enter image description here

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Have a good look at Toool's website - these guys brought bump picking to the public. Their video, whatthebump is very revealing :-)

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Thanks rory - but my question is more of "can I tell by looking at my new locks if they are bump proof?" – themerlinproject Mar 24 '11 at 5:31
From the outside, no. The few locks made specifically to be bump proof tend to have marketing stating that fact, so look for that sort of information (caveat - some advertised as bump proof, arent...) – Rory Alsop Mar 24 '11 at 8:23

Basically, if your key looks regular (=standard) then it is likely that it is not a bump proof key. The cheap advice if you want a "bump proof door", is to couple a security (=hard to bump) mechanic key with a magnetic lock (with a RFID card for instance).

However, you can find some really resistant keys. I guess the most well known in North America is the second generation Bilock key. Another star key is the anker magnetic key, almost impossible to copy, very difficult to lock pick.

To tell the truth, if you have an anker key, an armored door and a 12 points lock, most thieves will prefer destroy the wall next to the door to enter your house (I actually saw that at the office).

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Test to see if your lock is bump-proof by putting your key in, give it turning pressure and push it all the way in. If the key jams, it's bump proof. If the key turns you need new locks. I am a former thief, but I'm now a lock smith. Look out for lock snapping on the useless PVC doors -- it's much more common than bumping. Lock snapping is what you need to protect yourself from.

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What is lock snapping? – Niall C. Jul 12 '13 at 17:07
Applying force to the lock so it breaks. – Steven Jul 12 '13 at 20:11

This technique is very efficient and it's scary to learn how easy it is for burglars to enter your home this quickly and virtually without any noise or sign of forced entry .Anyway, there are some things you can do to prevent this from happening to you: -Modifying your existing locks and deadbolts is a cost effective way to make your locks more secure. A certified locksmith is able to make modifications.This option makes bumping somewhat more difficult but not impossible. -If security is paramount and you want to sleep comfortably with the knowledge that your house is officially bump-proof, you can install new high security locks. -Another option is installing non tumbler locks such as rotating disk locks, or magnetic / electronic locks.

These are just a brief introduction, for more detailed info visit this. link

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