Shouldn't These Be Red?

I am currently having trouble with this achievement: I am on my 6th playthrough of the DLC shooting every barrel in site and have yet to unlock it. Anyone have any tips?

I have not seen any particular issues with this specific achievement, but this game is rife with buggy achievements so I'm not surprised.

My only advice would be to do a fresh playthrough and manually count you have shot and exploded 50 red barrels. Barring that a fresh reinstall might help with the tracker seeing you have indeed hit 50.