It's an enlisted Army hat badge but I think it's newer. It looks like the 60's to 70's style. The newer ones came with a coating on them and that still has the coating on it. You can see it starting to wear away. When I was in basic in 76 we had to strip it away with brasso so it would shine.
They still do on hats. The screwbacks on DUI's and rank all went away for the most part in the mid 40's but there was still some private purchase stuff that was screwback. I have seen a few from the early 50's but they aren't real common.