"Fuhst" - carrying Hollywood accents too far

At the beginning of the Gunsmoke radio show, Matt Dillon (William Conrad) said that he is "the first man the look for, and the last man they want to see." He pronounces it "fuhst," with that affected blue-blood accent that cannot bear to pronounce an "r." Do you think that a Kansas sheriff in the 1800s would have pronounced it that way?