Any locksmiths/safecrackers on here?

I'm guessing it's too late to help in any way, but I'm curious - what did you wind up trying?

The stethoscope thing isn't implausible - assuming you hear anything at all (I can't tell what materials were used, leaving me useless there) I doubt that any of the modern countermeasures ('false clicks' and so on) would have been installed. Also not entirely implausible is guessing - although there are bazillions of combinations, lock tolerances were (and sometimes still are) such that you don't have to get the number exactly right, and if the knob had literally not been moved out of the way at all in the last hundred years you have the last number already (long shot, I know, but... oh, well). A few warnings on the stethoscope thing... a very obvious, but still sometimes missed, problem is not making sure that all you'll be hearing is the safe (put a rather loud pocketwatch - for example, one like mine, apparently - on the thing and you might hear a *lot* of irrelevant clicking - not to mention the fact that should something loud happen to the safe you'll be quite uncomfortable), go *slowly*, expect to give it a few tries until you know very well what kind of sounds will be made (give the wheel a few spins in both directions before seriously starting (after noting the original position of the dial, just in case) to help with this a bit), *take notes*, and don't expect it to be fast.

Jeff
 
Jeff! STOP THINKING.

Also, in my experience, a sledgehammer works wonders for most locks, but for extreme variables such as noise and structural damage, might not be the best bet. I did slip a lock in my freshman year to my dean's office with a paper clip and a shoelace to avoid suspension. Kind of started a bit of a penetration fire in my experience. Alsop, for things like pin mechanisms, the pick attached to an electric toothbrush had worked in the pasta.
 
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