If you used generally accepted long term storage techniques I would definitely leave them where they are. Then I would go back in time and delete this post.
Posting how many rifles you have, that they are on your jointly owned land, etc. sort of defeats the purpose.
I am not saying you should have a secret cache of rifles unless there is an apocalypse, but if you do have one you shouldn't be telling anyone about it.
On the GPS:
Several years ago the Chinese blew up a satellite. I am sure most of you remember b/c the news made a big deal about it without going into details. Using weapons in space is supposed to be a no no even for testing, but space is a lot closer than say Washington State, so it isn't that hard to do. The Chinese were really just tired of us getting on international TV and bragging about how elite our troops with GPS were and about how no country in the world could defeat our advanced GPS technology. So China just lauged and pointed out that there are about a dozen countries that have the technology to create massive blind spots in our GPS system if the need to. How lost do you think our armed forces would be then? How many still know basic land nav?
US military can shut down GPS or lock access to mil only. They do one or the other quite often in the AM while a friend of mine is on balloon flights(sort of complicates the ground chase).
To the point, if you need these rifles there is a good chance GPS will be down. Tagging it for convenience might be a good idea, but have a back up plan.