Normally a 12" AA battery clock that one would put in a barn is the absolute rock bottom of the cost and quality curve. Like the going rate for one is less than $15 and in my local feed store less than $10. If that's what you are using you are just seeing the statistical deviation of these cheap mechanisms. If you want better time then Redleg06 has given you a good answer.

^Why then from the opening post: "But if put any of the 3 clocks someplace else they work just fine?"

quote:

Originally posted by gjgalligan:
. . .
I did put a new battery charger on the shelf near the clock but I think this all started before that.

...

That could certainly do it. Try moving that, or the clock somewhere else in the barn, and see if that makes a difference

There are like a million variables here. Some suggested above, many/most not even suggested. And no description of the someplace else to compare. What's the goal? A clock that runs well in your pole barn? Get a different clock.
Explaining the difference? Then document both environments in way, way, way, way more exacting detail and specificity. Conduct a number of isolation tests and then you can figure out the difference that is causing it.

quote:

Originally posted by kkina:
^Why then from the opening post: "But if put any of the 3 clocks someplace else they work just fine?"

Yes, most of the responders haven't fully read the OP.

My battery operated clocks that are outside just don't seem to work as well or last as long as those that are inside the house.

Aliens usually park their UFO in pole barns so as not be seen. They have metal in them that messes with time due to the proximity of the wormhole. This is simple stuff man, you didn't really need to post an entire thread on it.

quote:

Originally posted by Redleg06:
Or just get an atomic clock like this...

La Crosse Technology WT-3129S 12 Inch Atomic Analog Wall Clock

I have a couple of the 14" version of that clock (404-1235UA-SS). Runs on 2 or 4 C cells, if you install 4 batteries it is supposed to operate for up to 5 years. Solid clock and pretty much never off time wise.

https://www.amazon.com/gp/prod...n_title?ie=UTF8&th=1