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How To Open A Master Lock Box [Even If You Forgot The Combination]

Would you like to know how to open a Master Lock Box, even if you forgot the combination? Well, we have researched this topic and have the answers for you. Knowing how to open a Master Lock box without the cross is crucial if you forget it.

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To open a Master Lock Box without the combination, insert a Weiser shim on the bottom left of the first rotary wheel and spin it until you feel the shim move. Repeat this process for each rotary wheel. Now try opening the lock box and if it doesn't open, rotate all wheels one number and try again until it opens.

This article will teach us how to open a Master Lock Box without the combination. We will also learn the answers to other interesting related questions, such as how do you open a Master Lock without the key, and are there any locks that can't be picked?

Two broken master lock box with one opened, How To Open A Master Lock Box [Even If You Forgot The Combination]

How To Open A Master Lock Box [Even If You Forgot The Combination]

If you want to open a Master Lock Box without the combination, you'll need the right tool. A Weiser shim is the tool for opening a Master Lock Box without the combination. A Weiser shim is a thin piece of metal that doesn't easily bend when pushed.

Take your Weiser shim and insert it into the gap on the left side of the first rotary wheel near the bottom. Once you have inserted your shim, turn the dial until you feel a tiny kickback on the shim. This kickback signifies that the rotary wheel is aligned with the locking mechanism.

A brand new Master lock box mounted above the door lock

Now, repeat the same process for each of the other rotary wheels. Once you have aligned all the rotary wheels, try opening the Master Lock Box. It likely won't open, but you now have the rotary wheel aligned with each other.

Next, rotate each wheel one number in the same direction and try to open the box again. Keep turning each wheel by one and checking until the Master Lock Box opens.

If none of the rotations provide the correct combination, then you must repeat the first step. There's a chance one of your rotary wheels is off by one, so repeat these steps until you find the correct combination.

How do you open a Master Lock without the key?

A broken lock on a white background

There are several methods to open a Master Lock without the key. Let's examine some of the most popular and explain how they work.

Breaking The Lock

One traditional way to open a Master Lock is to break it open. To break open a Master Lock, you will need a hefty hammer.

You will want to take your large hammer and strike the top of the lock in a downward motion. The trick to this method is to apply enough force to overpower the locking mechanism and force the lock open.

Sometimes when using this method, the locking mechanism can become jammed, effectively breaking the lock closed. If this happens, you will need a pair of bolt cutters to remove the lock since the key will no longer work.

A master lock box mounted on the side of the concrete wall

Bumping The Lock

You will need a bump key when attempting to open a lock open. A bump key is a key where all of the cuts in the key are at their maximum depth. Bump keys are also called 999 keys because the deepest groove in keys is nine.

Once you have your bump key, insert it into your Master Lock. When the key is fully inserted, slowly slide it out until you feel it slide past one pin. Doing this will feel like a small amount of tension and then a release of tension.

For the next part, you will need something to strike the key. Hitting the key is why this method is called bumping, and a hammer or rubber mallet will work.

Now, bump the key with your hammer while applying a small force to turn the key towards unlocking. This bump will force all the pins up, and since you are applying turning pressure, the pins will get stuck in the open position.

If the lock doesn't open, you will need to try again. With practice, this method can be used to open a Master Lock in seconds.

Picking The Lock

When picking a lock, you must have the right tools. You will need a tension wrench and a pick. You can make a tension wrench and pick out of paperclips or bobby pins, but try a lock picking kit for the best results.

You can find this product here on Amazon.

Take your tension wrench and insert it into the Master Lock. You must apply torque to the tension wrench while picking the pins.

Take your pick and slide it into the back of the lock. Press down on the selection until you feel something push up. Your pick is aligned with a pin when you think something push up.

Push down on your pick to push the pin up into place. The tension wrench pressure will keep the pin from falling back down.

Now pull the pick out slightly to find the next pin. Keep pushing pin up until all the pins have been unlocked. Once the final pin is unlocked, your Master Lock will pop open.

A black Master lock box installed on a door

Are There Any Locks That Can't Be Picked?

There are not any locks that can't be picked. Lock makers are constantly inventing new methods to prevent lock pickers from picking their locks, but lock pickers keep developing new ways of overcoming their barriers.

While there aren't any locks that can't be picked, there are many locks that are built to be resistant to lock picking.

What Are The Best Pick-Resistant Locks?

A Master Lock box on the floor

While a lock that can't be picked may not exist, some locks are difficult enough to open that most lock pickers won't attempt to open. Let's look at some of the best pick-resistant locks and how they create trouble for lock pickers.

Schlage Primus Lock

A Schlage Primus lock uses two sets of pins to ensure that the lock is tough to pick. Keys for this type of lock have a second set of grooves on the side to align the other pins.

These locks also have a sidebar that is unlocked by pressing the key into the back of the lock. Keys for Schlage Primus locks have pointed ends to open this additional locking mechanism.

Medeco Lock

Medeco locks have a unique feature that makes them much more challenging to pick. Each Medeco lock's pins can rotate left and right, and each pin must be rotated correctly to open.

The pins are rotated by a key that has angled grooves that match the lock. Even if you made a bump key for this type of lock, you would need many variations of the bump key for each combination of angled grooves.

 The other feature of these locks is false channels. These false channels allow the pins to lift into them but won't let the lock open. These false channels can make picking a Medeco lock very frustrating.

Mul-T Lock

A Mul-T lock is appropriately named because it has multiple locking mechanisms to make lock picking nearly impossible. These locking mechanisms are its telescopic pin tumblers, locking bar, and alpha spring.

The telescopic pin tumblers in a Mul-T lock work like the tumblers in a standard lock but are cut more precisely. These pins make picking much more difficult to do by hand.

The Mul-T lock also uses a locking bar which works like an additional set of tumblers in the horizontal direction. A lock picker would need to pick both sets of pins simultaneously to open this kind of lock.

There is also an alpha spring in the key, which opens the keyway and engages a special release in the back of the lock. These additional locking mechanisms make picking a Mul-T lock nearly impossible.

Final Thoughts

Two broken master lock box with one opened

This article taught us how to open a Master Lock box with nothing but a Weiser shim. We also learned how to open a Master Lock without the key.

Remember, while no lock is pick-proof, some locks are very challenging to open.

We hope you enjoyed this article. If you want to learn more, check out some of these other posts.

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