Victor Mature wanted to join some posh club, and, when he was told that they didn't accept actors, he said "I'm not an actor, and, I have 50 movies to prove it."

How about Robert Newton? terrible actor, but, he IS Long John Silver!

Wayne Morris? Chester Morris? (Boston Blackie)
Morris Ankrum? Whit Bissel? Michael Rennie? The bad ones outnumber the good.