If you’re fashioning your own bump key, pick a key that you don’t use regularly. Try it out in a few cylinder locks to see if it fits before filing it to the right specifications. Lock bumping is such a potential problem because it can be performed with almost any key. [2] X Research source
When it comes time to modify the key, be careful not to file the valleys too shallow or deep. If the spaces between the teeth are not at the right depth, the key will be useless.
Locksmiths refer to keys that have been ground down to a serrated pattern with sharp, even peaks and valleys as “999 keys. ”[3] X Research source Pre-cut bump keys can also be bought from unscrupulous vendors, but be warned: possession of a bump key is generally regarded as a cause for criminal suspicion by law enforcement.
Locksmiths and services that grind key duplicates are capable of precisely cutting 999 keys, but you might get some strange looks if you ask for this to be done.
Keys of roughly the same size will often fit any lock with the same mechanism (like a cylindrical lock). [5] X Research source Insert the key slowly and carefully to make sure it doesn’t get stuck. The deeper valleys might make it prone to getting caught on the pins.
Don’t turn the key too hard. It will be weaker since you removed metal from the body, and twisting it forcefully while striking it might cause it to break off in the lock.
Hit the key directly on the end, not at an angle. The bump won’t work if the key is inserted all the way into the lock. Pull back on the key until you hear the first click before attempting the strike.
If you’ve tried over and over and still can’t get the key to turn, either the grooves you filed in the valleys are not the right length or the deadbolt needs to be turned in the opposite direction.
The markings themselves will vary, but may take the form of a vertical line, a plus sign or an Underwriter’s Laboratories (UL) seal of security. Ask a hardware specialist for tamper-proof designs when buying new locks.
If you have reason to be especially concerned about lockpicking, consider going with a different type of locking mechanism than the usual cylinder lock.
Commercial grade locks will be more expensive on average but provide more trustworthy home defense.
Leave a TV or lamp on in the front of your home at night or when you have to go out of town to make it appear that someone is home and awake. The majority of break-ins occur through the front door. Make sure you have locks secure enough to stop a brazen attempt to enter your home. [12] X Research source
