all hat and no cowboy

Full of talk that is more impressive than that which one actually possesses or is able to do. A variant of "all hat and no cattle." Primarily heard in US. He talks as though he knows more than anyone else, but he's all hat and no cowboy. Over the years, her political rhetoric has become all hat and no cowboy. She criticizes more than ever, but she gets less and less done each year! That disgraced CEO is all hat and no cowboy if he's saying he still has authority over the company.