At least according to professional jew and jew authenticator Nate Bloom, editor of the generally reliable, but oddly temorarily defunct
www.Jewhoo.com. In a 2003 jewishsf.com article, he answers the oft-pondered Bronson Question thusly:
"Tough-guy actor Charles Bronson, born Charles Buchinsky, died on Aug. 31, and no doubt many wondered, as they read his birth name in the obit, whether he was Jewish. No, he wasn’t. His parents were non-Jewish immigrants from the Ukraine and Lithuania, respectively. Like most actors of his generation, he dropped his ethnic name, lest it add to the many difficulties all actors face when they try to make a living at their craft..."
--http://www.jewishsf.com/content/2-0-/module/displaystory/story_id/726/format/html/edition_id/4/displaystory.html