Cool safe trick

Rob Boudrie

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As a practical matter, most three number dial Group II/IIm, and some Group I safe mechanical combination locks have a two number combination.

My proof of concept was with an S&G Group II, but this should work on all similar locks:
  1. Dial the combination as you normally would, but stop at 0 before you dial to the last digit.
  2. Dial to 20, then back to 95
  3. Dial to 21, then back to 95
  4. Dial to 22, then back to 95 --- repeat pattern until the fence drops into the gates and the cam engages
Do not go much below 95 as that will scramble the combination and lose the setting of the first two digits.

If you have a Group I, this will work only if the separate operation to drop the fence can be repeated without scrambling the wheel settings for the first two numbers.
 
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This is one reason why the old trick of "Make your safe quicker to open, dial the first two digits in ahead of time" is a really horrible idea.

Dial the combination as you normally would, but stop at 0 before you dial to the last digit.
  1. Dial to 20, then back to 95
  2. Dial to 21, then back to 95
  3. Dial to 22, then back to 95 --- repeat pattern until the fence drops into the gates and the cam engages
Speed hack: Work through the even-numbered digits first (20, 22, 24,...)
 

Rob Boudrie

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My point is that the combination space of these locks is claimed to be 1M possible, but is really much smaller. That trick gets it down to 10,000 and if you are going to work the tolerances (the aforementioned speed hack) like an autodialer would using 34 positions, you only have 1156 effective combinations for the first and second number, and can find the third number using this trick.
 

AJK129

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I have an old safe I have the combination for but won't open. Would this work or will I still have the same issue where it wont open after the combo?
 

Rob Boudrie

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This is one reason why the old trick of "Make your safe quicker to open, dial the first two digits in ahead of time" is a really horrible idea.
If you're going to do that, just set the safe to a single number opening (mechanical dials)
 

Rob Boudrie

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I have an old safe I have the combination for but won't open. Would this work or will I still have the same issue where it wont open after the combo?
It would work to check the last number. I suggest you try all combinations of +1, +2, -1, -2 with the first two numbers since the setting may have slipped. Basically, what Lucas already said combined with my trick for #3.
 

AJK129

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I had a safe like that. Try +1 or +2 from the combo you have. Like if the combo is 10/20/30 try 12/22/32.
It would work to check the last number. I suggest you try all combinations of +1, +2, -1, -2 with the first two numbers since the setting may have slipped. Basically, what Lucas already said combined with my trick for #3.
Thanks, theres some old stuff in there and I've been curious to see whats it is.
 

Gator9329

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Tried it again to see if it would pay out again and these two weird dudes jumped out and ran off with my beer

intro-1551725871.jpg


NOT EXCELLENT !!!
 

Spanz

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I have an old safe I have the combination for but won't open. Would this work or will I still have the same issue where it wont open after the combo?
my brothers gun safe had an issue that he had to dial the combination in like five times before he could get it to open.
the problem ended up the tumblers drifted slightly, and he had to move one of the numbers up one....like instead of turning to 31, dial to 32 instead. that fixed it.

so i would write down the combo, and try 1 higher and 1 lower, on each number, and it might pop open.
 

Fixxah

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One safe I know if needs five digits to actually open. Four to open the "gate" and turn back to allow the handle to turn. Really cool safe.
 

Rob Boudrie

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One safe I know if needs five digits to actually open. Four to open the "gate" and turn back to allow the handle to turn. Really cool safe.
S&G makes 4 wheel pack locks but you rarely see them in the wild.
 

Rob Boudrie

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