Weather resistant combo lock for geocaching

[WilsonTrucking]

Im getting ready to set up a multi stage geocache and had an interesting idea. I want to set the main cache as a .50 cal ammo can with a combo lock on it. Each number for the code will be hidden in seperate nano caches, and you would clearly have to find all 3 or 4 to open the lock.

So im going to need a robust, easy to use lock that can handle being outside in the elements year round with a shackle small enough to fit the hole on a standard military issue ammo can. Suggestions?

[gumptrick]

I don't know of any environmentally resistant combo locks otherwise I'd share.

But I do have a couple of ideas that could help: Instead of nano-caching the numbers to the combo, you could use a series of keys and normal padlocks instead. Nano-cache #1 contains the key that gets you into cache #2, which gets you into no. 3, etc. Another option would be to just put multiple keys in the nano-caches and put multiple locks on the ammo can. If multiple locks won't fit as-is then use a lockout-tagout adapter that lets you put multiple locks on a single hasp.

[WilsonTrucking]

The main issue with the key idea is the person woukd then have to retun all the keys to the original locations.

[gumptrick]

Ah, I hadn't thought about that.

Have you considered something like the Abus 180IB or the 160/50? These are from their "marine" line and are rated for weather exposure and salt water. You could cache individual numbers for each wheel, or you could cache numbers that would add up to the combination.

i.e., if the combination is 4-7-1-3 then you could cache a few numbers that add up to 4713 so the searchers would have to find all the nanocaches to add up to the correct total?

[WilsonTrucking]

Youve got the right basic idea. Lets say there are 4 numbers, 4 7 3 1. You hide the cache containing each number and the gps co ordinates of the next cache in the sequence. The coords for the first cache get posted and people find the first cache which has the first number for the combo and the coords for cache 2 and so on. Once youre at the main cache, you enter the combo and there you are.