Does a fighter with an increased crit range (say 19-20) always hit on a 19?

@stramesDoes a fighter with an increased crit range (say 19-20) always hit on a 19? Or does the fighter miss if the AC is too high? Only a roll of 20 is an automatic hit, unless a feature says otherwise.

— Jeremy Crawford (@JeremyECrawford) September 17, 2014

@stramesFYI, there is a debate going on http://tinyurl.com/llbcfgq And I fear that ‘unless feature says otherwise’ will fuel not settle I had a brain glitch and was thinking of a theoretical crit. range increase. Specifics: Improved Critical does score a hit on a 19.

— Jeremy Crawford (@JeremyECrawford) September 17, 2014