Yes. Get a suitable sized piece of oil-resistant PVC pipe. Put a couple of your pieces in it for ‘long term storage’. Fill it with clean motor oil taking care to make sure that all of the air is removed. Seal it.
Then geo-cache it somewhere that only you or your family will ever find it.
(-:
If it is the time to bury it, more than likely it is the time to use it...
Nice idea, but too complicated. Spray cans of canola oil, a vacuum packer and the PVC pipe is easier and neater. [Don’t use olive oil spray since it is slightly acidic.] When you open the sealed weapons, plain old rubbing alcohol will clean them right up for oiling and use. Of course this system would only be viable for under fifty year storage ...